Best REST API Client Tools for 2025

REST APIs power much of today’s digital infrastructure — from mobile apps and SaaS platforms to IoT devices and enterprise systems. Whether you’re testing a new endpoint, debugging integration issues, or documenting workflows, a reliable REST API client can make the process faster, more precise, and more collaborative.

This guide breaks down what REST API clients are, highlight the best tools available (both free and paid), and give you a framework for choosing the one that fits your needs.

What is a REST API Client?

A REST API client is a tool that allows developers to send HTTP requests (GET, POST, PUT, DELETE, PATCH) to an API and inspect the responses. Unlike manual methods such as curl, API clients streamline tasks by providing intuitive interfaces, request history, authentication helpers, and collaboration features.
Key capabilities include:

• Request Building: Easily compose requests with headers, parameters, and body data.
• Authentication Support: Handle OAuth 2.0, API keys, JWT, and Basic Auth without manual setup.
• Testing Automation: Create test suites, chain requests, and run regression checks.
• Environment Switching: Manage multiple configurations for dev, staging, and production.
• Collaboration: Share collections, mock servers, and documentation with your team.

Best REST API Client Tools

Here are the best REST API Client tools to consider:

1. Requestly

Requestly’s API Client blends the convenience of a lightweight request tester with the power of a debugging and mocking suite. Built for modern development workflows, it lets you send, inspect, modify, and mock requests without switching between multiple tools.

Features:

1. REST and GraphQL support with intuitive interface

2. Request interception and modification in real time

3. Built-in API mocking for testing without backend dependencies

4. Environment and variable management for multiple setups

5. Shareable collections and team collaboration tools

6. Integrates with Requestly’s request/response rewriting and debugging tools

• Pros: Free, Open-source, Combines testing, mocking, and debugging in one platform
• Cons: Some advanced collaboration features require a paid plan
• Best For: Developers who want a single tool for API testing, mocking, and debugging

2. Postman

Postman is the most widely used REST API client, offering robust request building, automated testing, and integrated documentation in a single platform. It has grown into a full API development ecosystem that supports REST, GraphQL, and gRPC, making it suitable for both solo developers and large enterprise teams.

Features:

1. Collections for organizing requests

2. Environment variables for quick switching between setups

3. Pre-request scripting and automated testing

4. Built-in mock servers for rapid prototyping

5. API monitoring and performance tracking

6. Supports REST, GraphQL, and gRPC

• Pros: Large community, extensive integrations, user-friendly
• Cons: Can be heavy for simple use cases; advanced features require paid plans
• Best For: Teams needing a comprehensive, all-in-one API platform

3. Insomnia

Insomnia is a clean, developer-focused REST and GraphQL client with a strong plugin ecosystem. Its minimalist UI hides a powerful feature set, making it equally useful for quick testing or more complex automated workflows.

Features:

1. Multi-protocol support including REST, GraphQL, and gRPC

2. Environment variables and secrets management

3. Cookie jar support and authentication helpers

4. Plugin system for extending functionality

5. Request chaining for automated workflows

• Pros: Lightweight, open-source core, strong GraphQL features
• Cons: Cloud sync and collaboration require paid tier
• Best For: Developers who want speed and simplicity

4. Hoppscotch

Hoppscotch is an open-source, browser-based API client that loads instantly and works offline as a PWA. It focuses on speed, accessibility, and easy sharing of requests without heavy setup.

Features:

1. Web-based with instant access (no install required)

2. Progressive Web App (PWA) for offline use

3. REST, GraphQL, and WebSocket support

4. Request history and sharable request links

5. Keyboard shortcuts for power users

• Pros: Lightweight, fast, open-source, works anywhere
• Cons: Limited automation and testing capabilities
• Best For: Quick API checks and lightweight everyday testing

5. Bruno

Bruno is a privacy-first, local-only API client where data is stored as plain text files, making it ideal for version control and offline workflows.

Features:

1. Local-first storage with no cloud dependency

2. Git-friendly JSON/YAML collection format

3. Works fully offline for secure environments

4. High performance and minimal footprint

5. No telemetry or data tracking

• Pros: Privacy-first, great for secure workflows, version control ready
• Cons: Lacks native team collaboration features
• Best For: Security-conscious developers and air-gapped environments

6. Apidog

Apidog combines API design, documentation, testing, and mocking in a single unified platform. It’s built for teams who want to manage the entire API lifecycle without juggling multiple tools.

Features:

1. API design, documentation, and testing in one tool

2. OpenAPI import/export

3. Auto-generated documentation hosting

4. Mock servers for prototyping

5. Automated test case generation and execution

• Pros: End-to-end API lifecycle management, strong documentation tools
• Cons: May be overkill for simple workflows; some features require paid plan
• Best For: Teams that manage API design and testing in one platform

7. Paw (macOS)

Paw is a native macOS REST API client with a polished UI and advanced scripting capabilities, catering to developers who want a premium, platform-optimized experience.

Features:

1. Native Mac client with smooth OS integration

2. Dynamic values and scripting hooks

3. Code generation in multiple languages

4. Visual request builder with rich UI

5. Plugin support for customization

• Pros: Beautiful design, Mac-optimized, automation-friendly
• Cons: Mac-only, requires purchase
• Best For: Mac developers who want a premium native experience

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How to Choose the Best REST API Client for your Needs?

Here are some practical considerations to help you select the right REST API client:

• Protocol Support: Determine whether you only need REST support or also require compatibility with other protocols such as GraphQL, gRPC, or WebSockets.
• Collaboration: Consider whether you will be working alone or need features that allow you to share collections, environments, and test results with teammates.
• Automation: Evaluate if you need built-in support for CI/CD integration, scheduled tests, or automated workflows to streamline your development process.
• Platform Compatibility: Check if the client works on your preferred platform, whether it’s a desktop application, web-based tool, command-line interface, or OS-specific software.
• Security: Decide if you require offline or local-first storage to protect sensitive data, especially when working in secure or restricted environments.
• Budget: Review the free tier to see if it meets your needs, or determine if the additional features in a paid plan justify the cost.

Why Requestly’s API Client Deserves a Spot on Your List

Requestly’s API Client is a modern, developer-friendly tool that blends the simplicity of a lightweight API tester with advanced debugging capabilities. Unlike traditional clients, it’s built with request interception and modification at its core — meaning you can mock APIs, rewrite requests/responses, and simulate network conditions without leaving your workspace.

Features:

• REST and GraphQL support with an intuitive interface
• Request interception and modification in real-time
• Built-in API mocking for development without backend dependencies
• Environment management for dev, staging, and production
• Shareable collections and team collaboration features
• Works seamlessly alongside Requestly’s browser and desktop debugging tools

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Conclusion

The best REST API client depends on your workflow, team size, and priorities. By matching a tool’s strengths to your requirements, you can streamline development, improve testing speed, and collaborate more effectively.