Best API Design Software for Startups

KrakenD

KrakenD is a high-performance API Gateway optimized for resource efficiency, capable of managing 70,000 requests per second on a single instance. The stateless architecture allows for straightforward, linear scalability, eliminating the need for complex coordination or database maintenance. It supports various protocols and API specifications, with features like fine-grained access controls, data transformation, and caching. Unique to KrakenD is its ability to aggregate multiple API responses into one, streamlining client-side operations. Security-wise, KrakenD aligns with OWASP standards and doesn't store data, making compliance simpler. It offers a declarative configuration and integrates with third-party logging and metrics tools. With transparent pricing and an open-source option, KrakenD is a comprehensive API Gateway solution for organizations prioritizing performance and scalability.

66 Ratings

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Kinective Bridge

Kinective

With Kinective Bridge™ (formerly OmniConnect), easily connect your core with best-of-breed fintechs to scale digital transformation, modernize operations, and increase client delight. Transformation sounds great on paper, but hard to make a reality with legacy tech stacks and outdated infrastructures. The hassle of switching cores or burning through in-house dev hours to integrate systems can be a slow, time-consuming process. To thrive in today’s modern, digitally-focused world, you need one connection to scale your transformation efforts quickly and securely. Kinective has the connections you need. Our Kinective Bridge™ (formerly OmniConnect) solutions give you control by bridging the gap between legacy systems and modern digital services through 80+ turnkey fintech integrations across 99% of US-based cores.

54 Ratings

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Postman

The collaboration platform for API development. Simplify each step of building an API and streamline collaboration so you can create better APIs—faster. Postman is a collaboration platform for API development. Postman's features simplify each step of building an API and streamline collaboration so you can create better APIs—faster. Quickly and easily send REST, SOAP, and GraphQL requests directly within Postman. Automate manual tests and integrate them into your CI/CD pipeline to ensure that any code changes won't break the API in production. Communicate the expected behavior of an API by simulating endpoints and their responses without having to set up a backend server. Generate and publish beautiful, machine-readable documentation to make your API easier to consume. Stay up-to-date on the health of your API by checking performance and response times at scheduled intervals. Provide a shared context for building and consuming APIs, and collaborate in real-time.

25 Ratings

Starting Price: $12 per user per month

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Azure API Management

Microsoft

Manage APIs across clouds and on-premises: In addition to Azure, deploy the API gateways side-by-side with the APIs hosted in other clouds and on-premises to optimize API traffic flow. Meet security and compliance requirements while enjoying a unified management experience and full observability across all internal and external APIs. Move faster with unified API management: Today's innovative enterprises are adopting API architectures to accelerate growth. Streamline your work across hybrid and multi-cloud environments with a single place for managing all your APIs. Help protect your resources: Selectively expose data and services to employees, partners, and customers by applying authentication, authorization, and usage limits.

1 Rating

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Xano

Xano provides a fully-managed scaleable infrastructure to power your backend. On top of that security, you can quickly build the business logic that powers your backend without a single line of code or use one of our pre-made templates to launch quickly without sacrificing scale or security. Build custom API endpoints without a single line of code. Accelerate time to market using our out-of-the-box CRUD operations and Marketplace extensions and templates! Your API comes “ready-to-use” so you can immediately connect to any frontend and focus on your business logic. Everything is also automatically documented in Swagger so connecting to a frontend is a breeze. Xano uses PostgreSQL which provides the flexibility of a relational database along with the Big data needs of a NoSQL solution. Add features to your backend in a few clicks or start with ready-made templates and extensions to jumpstart your project.

1 Rating

Starting Price: $29 per month

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Apidog

Apidog is a complete set of tools that connects the entire API lifecycle, helping R&D teams implement best practices for API Design-first development. Design and debug APIs in a powerful visual editor. Describe and debug easily with JSON Schema support. Automate API lifecycle with Apidog's test generation from API specs, visual assertion, built-in response validation, and CI/CD. Generate visually appealing API documentation, publish to custom domain or securely share with collaborative teams. Local and cloud mock engine generate reasonable mock data according to field names and specifications without writing scripts. Quality tools have the power to unite your entire team, while ensuring that no task is needlessly repeated. Effortlessly describe your API as you test it, and generate JSON/XML schemas with a simple click. Generate test cases from APIs, add assertions visually, and create test scenarios with branches and iterations easily.

1 Rating

Starting Price: $9 per user per month

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BuildShip

BuildShip is a lowcode visual backend builder that lets you ship APIs, scheduled jobs, AI workflows, cloud jobs instantly. Connect with any database, tools and AI models to create complete backend logic flows. Use prebuilt nodes or use AI to create custom logic nodes just for you. By combining the ease of nocode with power of low-code extensibility - BuildShip gives you a scalable way to build your backend fast. Supports powerful use-cases like: 💸 Collect payment and trigger Stripe, RevenueCat, Lemon Squeezy for subscription workflows 🪄 Trigger AI workflows and build AI apps' backend 🔌 Creating APIs for processing your data and CRUD ops on database 📝 Send form submission data to third party tools 🤖 Add AI Assistant Chatbot with OpenAI, Azure, Claude, Groq or any model 💌 Email users, generate leads, enrich data The possibilities are endless with BuildShip ✨

1 Rating

Starting Price: $25 per month

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WSO2 API Manager

WSO2

One complete platform for building, integrating, and exposing your digital services as managed APIs in the cloud, on-premises, and hybrid architectures to drive your digital transformation strategy. Implement industry-standard authorization flows — such as OAuth, OpenID Connect, and JWTs — out of the box and integrate with your existing identity access or key management tools. Build APIs from existing services, manage APIs from internally built applications and from third-party providers, and monitor their usage and performance from inception to retirement. Provide real-time access to API usage and performance statistics to decision-makers to optimize your developer support, continuously improve your services, and drive further adoption to reach your business goals.

1 Rating

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IBM API Connect

IBM

IBM API Connect is a scalable API solution that helps organizations implement a robust API strategy by creating, exposing, managing and monetizing an entire API ecosystem across multiple clouds. As businesses embrace their digital transformation journey, APIs become critical to unlock the value of business data and assets. With increasing adoption of APIs, consistency and governance are needed across the enterprise. API Connect aims to help businesses to get new features to market fast, maintain continuous availability, meet changing user needs, and spur innovation.

1 Rating

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Directus

Monospace Inc

Directus is an Open Data Platform for managing the content of any SQL database. It provides a powerful API layer for developers and an intuitive App for non-technical users. Written entirely in JavaScript (primarily Node.js and Vue.js), Directus is completely open-source, modular, and extensible, allowing it to be fully tailored to your exact project needs. With Directus Cloud, we've taken our open-source spirit to the cloud by offering Directus Community Cloud, a completely free tier - without quotas or limitations. It's ideal for hobby projects and demos, and when you're ready for production, Standard Cloud has the power and infrastructure options you need. Our pricing is usage-based, which means you only pay for what you use. Use Directus on your next headless cms, internal tool, or SaaS project, or use our Insights for better data management and analytics. With Directus, you're only limited by your imagination.

Starting Price: Free

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SyncTree

Ntuple

SyncTree strives to be a "Super Connecting Platform" that can easily connect any services you want. With SyncTree, which consists of SyncTree STUDIO, a solution for building backend business logic with block coding, and Block Store, a platform for buying and selling pre-made backend function blocks like App Store, you can organically utilize data and connect services to achieve unlimited service expansion. Based on aPaaS, Block Store provides APIs from various services such as ChatGPT, DALLE, YouTube, etc. in the form of 'backend function blocks', which you can subscribe to and then combine as you want quickly in SyncTree STUDIO to build your business logic. SyncTree is for everyone, whether you're an individual or a business, and you can subscribe and use it according to your needs, from the free version to the PRO version.

Starting Price: Free/1Month/3,000 Call

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Treblle

Treblle: A lightweight SDK for accelerated REST-based API development, see metadata for every API request with real-time API traffic monitoring, get powerful analytics and API governance features alongside API automated docs, and automated API security audits for every single request. Simplify workflows, enhance security with support for 18+ languages and frameworks for seamless integration. Empower your teams to build, ship, and maintain APIs faster.

Starting Price: $99 per month

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DreamFactory

DreamFactory Software

DreamFactory Software is the fastest way to build secure, internal REST APIs. Instantly generate APIs from any database with built-in enterprise security controls that operates on-premises, air-gapped, or in the cloud. Develop 4x faster, save 70% on new projects, remove project management uncertainty, focus talent on truly critical issues, win more clients, and integrate with newer & legacy technologies instantly as needed. DreamFactory is the easiest and fastest way to automatically generate, publish, manage, and secure REST APIs, convert SOAP to REST, and aggregate disparate data sources through a single API platform. See why companies like Disney, Bosch, Netgear, T-Mobile, Intel, and many more are embracing DreamFactory's innovative platform to get a competitive edge. Start a hosted trial or talk to our engineers to get access to an on-prem environment!

Starting Price: $1500/month

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Gravitee.io

Gravitee.io is the easiest to use, most performant and cost-effective Open Source API Platform that helps your organization to secure, publish and analyze your APIs. Use the power of Gravitee.io to manage identities with our OAuth2, OpenID Connect (OIDC) and Financial-grade API (FAPI) certified server. Gravitee.io APIM is a flexible, lightweight and blazing-fast open source API Management solution that helps your organization control finely who, when and how users access your APIs. With strong governance features such as API review and API quality and our market leading API designer, Gravitee.io enables you to design, manage, deploy and monitor your APIs in a secure and governed way. A branded Gravitee.io portal enables your API consumers to fully engage with your business - delivering high quality engagement for your business in the digital age.

Starting Price: $2500 per month

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Stoplight

Stoplight is an API Design, Development, and Documentation platform. Use Stoplight Platform to enable consistency, reusability, and quality in your API lifecycle, all with an easy, enjoyable developer experience. Here's what you can do with Stoplight Platform: - Design APIs with our easy visual designer, Stoplight Studio - Mock API designs automatically with Stoplight Prism mocking - Collaborate on your designs and invite internal and external users to provide feedback - Develop faster and better APIs - Test and enforce against style guides with Stoplight Spectral - Document both internal and external APIs automatically to create a delightful experience Utilize and integrate design-first workflows to quickly scale up standardized, collaborative, and well-governed API programs.

Starting Price: Free

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SwaggerHub

SmartBear

SwaggerHub is an integrated API design and documentation platform, built for teams to drive consistency and discipline across the API development workflow. Accelerate your team’s design process without any loss in quality or organizational style consistency with a powerful Editor that’s fully compliant with the latest Swagger (OpenAPI) standards. A Powerful Editor equipped with smart error feedback and syntax auto-completion. Style Validators for ensuring design consistency across multiple APIs. API Mocking to virtualize operations without any code. Domains for storing, reusing and referencing common OAS syntax across multiple APIs. Have your API design and development centralized on a single location, allowing your teams to seamlessly collaborate on new APIs, or discover existing APIs on a centralized platform. Coordinate your entire API lifecycle from a central internal repository, hosted on the cloud.

Starting Price: $90 per month

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RepreZen API Studio

RepreZen

Build APIs that click with client apps. RepreZen API Studio is an integrated workbench that brings API-first design into focus for your whole team, harmonizes your API designs, and generates APIs that click into client apps. Effortlessly. Full-featured OpenAPI editor with content assist, customizable templates, outline navigation & more for fast, focused API design. Live documentation view gives you immediate clarity & insight from the API user's perspective. Interactive diagram lets you visualize the API as you design. Generate & view in any browser to give API users a fast, intuitive overview. Split a large Swagger API spec into multiple files, even share & reuse API components across projects & teams! Edit, navigate, document & generate, all fully compliant with OpenAPI standards. Consolidate & simplify complex multi-file projects to a single file, for easy downstream code generation & docs presentation.

Starting Price: $22 per month

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StepZen

StepZen provides a unique low code approach to creating GraphQL APIs for any data source—REST, SQL, NoSQL, SOAP/XML, and GraphQL. With one command, you can specify your backend; StepZen introspects it and generates the schema for you. Then, with a few lines of code and powerful directives (@rest, @dbquery), you can quickly customize a schema—or write one from scratch. Another directive (@materializer) lets you stitch graphs together, seamlessly scaling GraphQL across teams and domains. In addition, by using @materializer, you avoid managing concerns across subgraphs, writing stubs of types, and other complexities. Whether you deploy a single graph or a federated graph-of-graphs, with one command, you deploy it to StepZen's highly available cloud. Automatic parallelized execution, security and control of your APIs and data, and performance and reliability optimizations are built-in. So we keep your GraphQL infrastructure secure and stable so you can focus on your business.

Starting Price: Free

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Metatype

Build modular APIs with zero-trust and serverless deployment, no matter where and how your (legacy) systems are. And castle building is hard. Even the best teams can struggle to build according to the plans, especially with the ever-evolving needs and tech landscape complexities. Typegraphs are programmable virtual graphs describing all the components of your stack. They enable you to compose APIs, storage, and business logic in a type-safe manner. Typegate is a distributed HTTP/GraphQL query engine that compiles, optimizes, runs, and caches queries over typegraphs. It enforces authentication, authorization, and security for you. Install third parties as dependencies and start reusing components. The Meta CLI offers you live reloading and one-command deployment to Metacloud or your own instance. Metatype fills a gap in the tech landscape by introducing a new way to build fast and developer-friendly APIs.

Starting Price: Free

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Firecamp

Navigate effortlessly through a clean and clutter-free interface, allowing you to focus on what truly matters—efficiently testing and collaborating on APIs. With a user-friendly interface and a range of powerful features, Firecamp streamlines the API development workflow and enhances collaboration among team members. Set values in variables to reuse in the whole platform dynamically. Publish beautiful API documentation for your team and community. Run API Collection Tests in the terminal or set in CI/CD pipeline. Test and debug your auth endpoints with a range of supported auths.

Starting Price: Free

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Testfully

From powerful API client features to advanced testing and monitoring, Testfully does it all. Enjoy the flexibility of cloud and offline-only storage, seamless team collaboration, and easy migration, all in one multi-platform tool. Easily transfer your data from Postman or Insomnia directly into Testfully. Flexible and secure, set global, environment, and folder variables scoped to workspace or user. Customize auth, parameters, headers, and body to build any HTTP request easily. Work together effortlessly, add teams, assign roles, and control folder access. Supports major schemes like OAuth2 for secure and streamlined authorization. From basic to complex, Testfully enables quick, effective testing without the need for coding, making advanced API testing accessible and hassle-free. Execute all requests in a folder simultaneously, sequentially, or randomly with just one click. Validate responses and perform contract testing using a declarative format, no coding is needed.

Starting Price: $49 per month

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Redocly

Beautiful API documentation loved by teams and API consumers. At last, API documentation your whole team will be proud of. Publish beautiful API reference docs in seconds and style them in minutes. Tick every developer's favorite box right out of the box, three panels, a try-it console, generated code samples, SEO-friendly, even friendlier search. Nobody likes outdated docs and scope creep. Maintain API documentation with your favorite source control integrated with our cloud app workflows. We support them all, including on-premise and API management providers. Launch a developer portal in minutes reusing your API definitions as assets. Add tutorials, quick-start guides, and developer tooling with incredible customization. Validate, lint, and bundle multi-file API definitions. Write always on-spec OpenAPI documents. Plug in your API reference and customize every nook & cranny to wow your API consumers.

Starting Price: $69 per month

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Specmatic

Experience the power of contract-driven development to confidently develop and independently deploy your microservices and micro frontends faster. Shift left and kill integration tests by leveraging API specifications as executable contracts to identify compatibility issues between your microservices early in your development cycle. Embrace parallel development, slash cycle times, and deliver products to market faster than ever before. Integration issues are minimized as the project goes through integration testing, ensuring a smoother more robust, and efficient process. Keep your front and backend teams in sync easily by collaborating on API designs and specifications. Turn your API specification into tests fast and for free (no code) and run them against your services to identify integration issues early. Identify backward incompatible changes just by comparing two versions of your API specifications with our unique “no code” approach.

Starting Price: $445 per month

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Mocki

If you want to create a simple API for testing purposes, simply enter a response body and get your custom API URL. Use Mocki to create a fully-fledged mock API. Using Mocki you can create, run, and deploy mock APIs. Use your mocks to design your API, serve static responses, simulate error scenarios, and remove dependencies to external services. Sign up today for a free 7-day trial. Sync your service with your code repository to keep your mock service up to date with the latest changes without manual steps. Using our managed hosting solution your mock service is always available for any consumer. Access a dashboard to gather insights on how your mock service is used. Using our open source CLI you can run your services locally. This enables you to run your service without requiring an internet connection to reach external services. A mock API can also be useful when testing backend apps. A common case is that your API or service needs to call external services over HTTP.

Starting Price: $15 per month

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Sparrow

Sparrow offers a complete set of tools that facilitate the entire API lifecycle, directing R&D teams toward excellence in API design-first development. Use cURL to send API requests, and support methods like GET and POST. It simplifies interacting with APIs, handling headers, data, and authentication easily. A collaborative open source solution for API development, streamlining the creation of exceptional APIs. By collaborations, developers can shift their development practices earlier in the process, leading to higher-quality APIs and faster development. Experience effortless parallel testing across diverse environments so you get the insights on the go. Sparrow offers powerful tools for securing and managing your API data along with self-hosting capabilities, providing users with complete control over their testing environment. Stay updated with Sparrow's latest developments, insights, and resources.

Starting Price: Free

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Flowcode

The simplicity of visual programming and the power of traditional coding. Flowcode lets you build fast and handles the infrastructure. So you can focus on solving the hard logic problems. Drag-and-drop functionality meets powerful logic-based nodes. Visually trace your API calls to find bugs faster. Manage versions, rollbacks, and updates effortlessly. Combine and orchestrate multiple AI models to build customized AI APIs. Flowcode is built on Flyde, an open source visual programming language. Flyde runs in VS Code and integrates with existing TypeScript code, browsers, and Node.js. Handle simple tasks quickly with visual flows. Dive deep into complex logic with custom code nodes. You can export your data and APIs and run them on your own servers. Stay flexible and independent. Easily handle database tasks with abstracted PostgreSQL or connect to other databases for more advanced needs.

Starting Price: $19 per month

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Hoppscotch

Hoppscotch LTD.

Hoppscotch makes it easy to create and test your APIs, helping you to ship products faster. Create APIs faster, test them instantly, document and share them automatically. From prototyping to production - develop without switching tabs. Hoppscotch got everything you need to make API development easy. Create workspaces for your teams. Control access to your workspaces. Work together with your team in real-time. Deploy Hoppscotch on your own servers. Organize your requests in collections or folders and share them with your team. Manage your environment variables and use them everywhere. View and manage your request history. Modify headers, authenticate requests, generate random data, and much more. Test your APIs and write assertions for the response. Use Hoppscotch in your native language. We support 30+ languages. Track all the activities in your workspace. Who did what and when. Use your existing SSO provider to login to Hoppscotch. Manage your users, workspaces, and more.

Starting Price: $19 per user per month

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NoCodeBackend

NoCodeBackend is a user-friendly, AI-powered platform that enables the rapid development of production-ready APIs without writing any code. Users can quickly configure databases, tables, and columns through an intuitive interface, with the system automatically generating corresponding API endpoints. NoCodeBackend's AI-assisted prompt technology allows users to describe their desired API functionality, and the system takes care of the rest, streamlining the development process. Additionally, NoCodeBackend offers automated documentation generation using Swagger, ensuring clear and comprehensive API documentation for a seamless developer experience.

Starting Price: $49 per month

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Boomi

Dell

Dell Boomi AtomSphere is the easiest way to integrate all your business applications. A single-instance, multi-tenant integration platform as a service (iPaaS), Dell Boomi AtomSphere gives enterprises and their teams access to full set of capabilities that speed up integrations and simplify management. With its visual design interface and enterprise-grade performance, Boomi AtomSphere can ensure scalability and high availability and provide support across all your app integration needs.

Starting Price: $550.00/month

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PrestoAPI

Eliminate the need for back-end development. Easily connect to your database using the connection string or server address. Customize your API methods by choosing the data to create, read, update, or delete. Presto! Your API is ready for use by your front-end development team. No back-end necessary. PrestoAPI currently supports SQL Server, MySQL, PostgreSQL, MongoDB, and Oracle database systems. Assign roles to users throughout the application or to specific projects. PrestoAPI is secured through Identity Server, OAuth 2.0, and Active Directory.

Starting Price: $49 per month

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Compare the Top API Design Software for Startups as of April 2025

What is API Design Software for Startups?

KrakenD

Kinective Bridge

Postman

Azure API Management

Xano

Apidog

BuildShip

WSO2 API Manager

IBM API Connect

Directus

SyncTree

Treblle

DreamFactory

Gravitee.io

Stoplight

SwaggerHub

RepreZen API Studio

StepZen

Metatype

Firecamp

Testfully

Redocly

Specmatic

Mocki

Sparrow

Flowcode

Hoppscotch

NoCodeBackend

Boomi

PrestoAPI

Best API Design Software for Startups

Compare the Top API Design Software for Startups as of April 2025

What is API Design Software for Startups?

KrakenD

Kinective Bridge

Postman

Azure API Management

Xano

Apidog

BuildShip

WSO2 API Manager

IBM API Connect

Directus

SyncTree

Treblle

DreamFactory

Gravitee.io

Stoplight

SwaggerHub

RepreZen API Studio

StepZen

Metatype

Firecamp

Testfully

Redocly

Specmatic

Mocki

Sparrow

Flowcode

Hoppscotch

NoCodeBackend

Boomi

PrestoAPI

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