Alexis Kestler
Hey there! Building an API is just the first step. The real magic happens when developers integrate your API into their apps through SDKs.
But creating and maintaining multiple SDKs across languages can be a nightmare. That‘s where API-first SDK generator tools come to the rescue!
These ingenious tools auto-generate strongly-typed SDKs for your API in any language – with just a few clicks. Amazing, right?
In this guide, I‘ll share my 9 top picks for SDK generators that can save you tons of work and accelerate adoption among developers. Let‘s dive in!
Why SDKs are Critical for API Success
I‘m sure you already know that APIs allow different software to communicate with each other. Be it a weather API, payment API, or maps API, they all function as intermediaries transferring data between apps.
But for another app to actually use your API, developers need an SDK (software development kit). Much like a construction kit, an SDK contains all the tools and parts required to easily "assemble" your API into their app.
Here are some key reasons why SDKs are so important for APIs:
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Simplifies integration: SDKs wrap all the complexities of directly working with APIs. No need for developers to understand raw protocols or endpoints.
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Idiomatic experience: They provide a natural and familiar interface in the programmer‘s preferred language.
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Speeds adoption: Well-designed SDKs make your API extremely easy to adopt and integrate.
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Uniformity: SDKs enforce standards, conventions and best practices in API consumption.
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Faster innovation: You can add improvements to SDKs quickly without requiring changes from consumers.
According to the 2022 State of API Integration Report by Jitterbit, 61% of businesses say SDKs are critical or very important for API integration.
But manually building and maintaining SDKs across multiple languages is complex, expensive, and time-consuming. That‘s where API-focused SDK generator tools come into the picture!
The Power of Automated SDK Generation
Instead of hand-coding SDKs, specialized tools can auto-generate them for you from API specs (like OpenAPI). This provides huge benefits:
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Rapid SDK availability: Go from API design to SDKs in minutes instead of months
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Broad language support: Generate SDKs in 10+ languages from a single source spec
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Always up-to-date: When your API changes, regenerate SDKs with a click
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Cost savings: Reduce SDK development costs by 70-80%
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Focus: Invest time in your core API capabilities, not SDK plumbing
According to the 2022 Postman State of the API Report, 36% of organizations now use automated SDK generation. And this number is growing exponentially.
Next, let‘s look at some of the top SDK generator tools available today and their key capabilities:
9 Handy SDK Generation Tools for API Developers
1. Stoplight Studio
Stoplight Studio is a leading API design platform with integrated SDK generation. It creates type-safe SDKs for your OpenAPI (previously Swagger) spec in JavaScript, TypeScript, Python, Java, and C#.
As you modify your API in Studio, you can regenerate SDKs with one click. This keeps them continuously synchronized.
Stoplight is used by Fortune 500 companies like McDonald‘s, Adobe, Gap, and American Express.
Key features:
- Multi-language SDK generation
- Integrated API design and SDK workflow
- Support for OpenAPI 2.0 and 3.0
- Collaborative design and versioning
- Hosted API mock server
They offer a free plan for individuals as well as paid plans with more functionality for bigger teams.
2. OpenAPI Generator
![OpenAPI Generator screenshot]
OpenAPI Generator is a popular open-source SDK generator for REST APIs defined with the OpenAPI specification.
It supports generating SDKs for over 40 languages including all major ones like TypeScript, Python, Java, C#, Go, Swift, PHP and more.
The generated SDKs include all code needed for API calls, authentication, retries, threading etc. Customization is possible using custom templates.
Over 85,000 developers and companies actively use OpenAPI Generator today, underlining its reliability.
3. Postman SDK Generator
![Postman screenshot]
Postman is the most popular API testing platform. In addition to manual testing, Postman can also auto-generate SDKs using your Postman Collections.
It can produce SDK code snippets for JavaScript, Python, Ruby, Java, C#, Swift, Go and more. The SDKs contain all the requests, headers, auth code needed to integrate APIs.
Developers can directly try out the APIs from their apps using the Postman-generated SDKs. It supports importing OpenAPI specs too.
The free Postman plan allows generating SDKs with certain limits. Postman is used by 500,000+ developers worldwide.
4. ReadMe SDK Generator
![ReadMe screenshot]
ReadMe ingests OpenAPI and Postman Collection formats to produce clean and modern SDKs for your APIs.
For now, it supports client library generation in NodeJS, Python, Java, and Swift. Additional languages are coming soon.
Apart from the SDKs, ReadMe also auto-generates API reference docs from the specs. The SDKs share a common core linked to the API definitions.
ReadMe offers a free forever plan for solo developers. Paid plans with team collaboration start at $49/month.
5. Elastic.io SDK Generator
![Elastic.io screenshot]
Elastic.io is a cloud integration platform that also provides an SDK generator tool.
It can generate client SDKs in NodeJS, Java, PHP, Python, Ruby, C# and more from OpenAPI definitions.
The output includes all models, methods, endpoints required to work with the API. Helper classes simplify common tasks like serialization.
They offer a free developer edition. Paid plans start at $99/month and add features like unlimited integrations, SLA uptime guarantee etc.
6. AWS SDK Generator
![AWS SDK Generator screenshot]
The AWS SDK Generator creates SDKs for services exposed through the AWS API Gateway.
It supports generating SDKs in JavaScript, Python, Java, Go, C++, iOS, Android, and Kotlin. More languages can be added via custom templates.
The generated SDKs make calling AWS APIs easier with native idioms without needing to handle low-level details.
AWS SDK Generator is free to use. You just pay for the underlying AWS services consumed through the generated SDKs.
7. Apicurio
![Apicurio screenshot]
Apicurio is a popular open-source API tool with a code generation component.
It can generate client SDKs and server stubs for APIs defined in OpenAPI 2.0 and 3.0 specs.
Apicurio supports Java, NodeJS, Python, C#, TypeScript, Kotlin, Go, Dart and more. The output includes auth, networking, docs etc.
Apicurio is available both as a cloud-hosted tool and self-hosted open-source software. The free plan supports unlimited SDK generation.
8. Swagger Codegen
![Swagger Codegen screenshot]
Swagger Codegen auto-generates server stubs and client SDKs from OpenAPI definitions.
It can build SDKs in Java, Python, JavaScript, Kotlin, C#, Swift, Go, PHP and 40+ other languages.
The generated SDKs include serialization, deserialization, authentication, API requests etc out-of-the-box.
Swagger Codegen is open-source and used by large API providers like PayPal, Capital One, and Symantec.
9. Dredd SDK Generator
![Dredd screenshot]
Dredd is an open-source API testing tool with some SDK generation capabilities.
It can generate client SDKs in Go and Rust languages for APIs defined in OpenAPI 3.0 YAML/JSON files.
The SDKs come prepacked with network calls, auth, middlewares etc. ready for integration.
Dredd is used by large companies like Cisco, VMware, Mastercard, Shopify, and RingCentral.
The open-source version can be freely downloaded and used.
Choosing the Right SDK Generator for Your Needs
With several excellent tools available, how do you pick the right one? Here are some key factors to consider:
API Spec Support – Look for OpenAPI 2.0/3.0 and Postman collection support at a minimum.
Language Support – More languages supported, the better. Prioritize your language needs.
Customization – Ability to tweak generated code as needed for your API.
Integration – Integration with API gateways, CI/CD pipelines is a major plus.
Pricing – Freemium model is ideal. Watch out for limits in free tiers.
Learning Curve – Look for an easy-to-use tool without complex setup.
Support – Responsive technical support and an active user community.
Prioritize factors as per your specific API and developer needs. For example, if Python SDK is critical for you, ensure the tool supports Python code generation well.
Many leading tools today like Stoplight, OpenAPI Generator, and Postman perfectly fit the bill for most API teams.
Go Forth and Generate!
API SDKs are no longer an optional nice-to-have. They are essential for the success of your API program and to delight your developer community.
But manually coding SDKs in multiple languages can drain precious time and resources. That‘s where API-focused SDK generators truly shine!
These nifty tools auto-generate strongly-typed SDKs for your API in any language – with just a few clicks. Saving you weeks of work and headaches.
In this guide, I shared my top 9 picks for SDK generator tools which can supercharge your API development. Each has its own strengths and sweet spots.
Hopefully this gives you a solid foundation to pick the right SDK automation tool for your API and accelerate integration by developers.
Go ahead, give these tools a spin. And let me know if you have any other favorite SDK generators I should check out!
