Comparing various API clients

Jump to Choosing the Right Tool if you do not want to be bored by the analysis. Also, special thanks to Step CI for their awesome list of API clients.

Introduction

APIs (Application Programming Interfaces) are the invisible engine of modern software, running everything from smartphone apps, websites, and entire industries (including banking & automotives). We regularly interact with them as developers – building, testing, and integrating them.

So, is there a way to evaluate APIs we are developing, or try APIs that we’ve recently discovered? Yes! That is where API clients come in – a core part of API workflows. However, choosing the right client from the multiple options can be tough.

Whether you need to collaborate with a team, give precedence to security and privacy, work offline, or just care about refining your workflow, understanding your options is necessary. By the end, you should have a clear understanding of each tool, enabling you to confidently choose what’s best for your project.

Postman: The de facto popular API client

Postman has been the industry standard for API development since a decade. It has an easy to moderate learning curve, has wide support for various API types (like REST, SOAP, GraphQL, gRPC), including real-time APIs (like WebSocket). Postman is serious about improving developer productivity and has a lot of features and tools that help throughout the API lifecycle: documentation, testing, mocking, monitoring and sharing.

Features

• A friendly UI that helps in sending requests and inspecting responses.
• Collections that help organise requests and documentation for better collaboration and reuse.
• Postman Cloud allows teams to collaborate and document APIs in workspaces. It also offers centralised version control.
• Documentation tools for generating API documentation more easily.
• Support for mocking & testing APIs by creating mock servers on the cloud.
• JavaScript (node.js based runtime) for pre-request and test scripts.
• Support for monitoring APIs by setting up schedules and viewing monitoring results on the cloud.

Postman has a proprietary, centralized cloud-first platform designed for team collaboration, and supports workspaces to facilitate real-time sharing between team members. However, it’s a freemium model, and comes at a cost. The free plan of Postman Cloud has a very limited feature set. To have the true team experience, you must upgrade to the Basic, Professional or Enterprise plans of Postman Cloud, which aren’t free, and pose privacy risks and vendor lock-in.

Pros

• Postman Cloud has Workspaces, a user-friendly team collaboration feature.
• Paid plans are enterprise-ready with extensive features, but free tier exists too.
• Filled with useful features, along with a lot of cloud-based features for collaboration and monitoring.

Cons

• Using Postman Cloud could lead to vendor lock-in and might also not suit all teams.
• Free tier is very limited, and larger teams would prefer not picking Postman for its cost.
• Postman client is resource intensive, requires account creation for full features, and depending on settings, stores data on the cloud automatically (doesn’t run offline).

Hoppscotch: The browser-based API client

Hoppscotch is the simplest web-based API client that runs as a PWA (Progressive Web App, so it can also run offline) in the browser. It’s not far behind when compared to Postman in terms of features and experience. It supports various API types (like REST, SOAP, GraphQL), including real-time APIs (like WebSocket, Server Sent Events, Socket.io & MQTT). They even recently released a desktop application of the API client, offering the same web-based experience on a desktop app (built with Tauri)

Features

• A friendly UI for sending requests and inspecting responses.
• Organises requests into Collections for better collaboration & reusability.
• Environments for storing and sharing environment variables with the team via the cloud.
• Real-time collaboration using Hoppscotch Cloud (supports self-hosting), with team workspaces for sharing collections and environments.
• Vanilla JavaScript for composing simple pre-request and test scripts.
• Experimental AI features for generating test scripts, request bodies, and API request titles.
• Migration supports importing and exporting Postman & cURL files.

Just like Postman, Hoppscotch also has a freemium pricing model, with an optional centralised cloud-first platform; however it also supports easy self-hosting using Docker. If you do not opt-in for the cloud platform, data gets stored offline, in browser local storage. This of course poses privacy risks and potential data loss.

Pros

• Good for teams working together directly, with real-time collaboration and easy sharing.
• Hoppscotch is browser-based, very accessible and lightweight.
• It’s also completely free and open source, with optional paid plans for extra features.
• Having a cloud account is optional. Hoppscotch can be used without cloud for basic features.

Cons

• Cloud-based collaboration is not very seamless, less mature than Postman.
• Larger teams might prefer picking optional paid plans for enhanced features.
• Browser-based nature of Hoppscotch might be self-limiting in advanced desktop workflows.
• Compared to fully offline tools, the browser-based nature also raises privacy concerns.

HTTPie: The CLI-based API client

HTTPie is a simple yet powerful CLI-based API client. While no CLI API client tool can beat cURL (having been at it since 1998) with respect to its extensive functionality, HTTPie mainly focuses on providing a developer-friendly command-line experience for making HTTP requests. It only supports HTTP (and by extension, REST) and no other API types. It’s designed for simplicity and readability in the terminal and doesn’t need any online connectivity. It’s primarily for individual use and shell scripting, with no built-in cloud or collaboration system. Collaboration usually involves the sharing of scripts or commands (via your favourite collaboration system).

Features

• Completely CLI-based operations. This makes it easy to integrate into shell scripting and automation situations.
• Using shell scripts allows for a highly extensible testing and scripting experience.
• No cloud or git integrations, so commands are only stored while writing them into a script file. By default, responses are not stored, data stays local and never leaves the device.
• Intuitive command-line experience for constructing HTTP requests in the terminal.
• Colorized and formatted output for easy readability.
• Session persistence for handling cookies and other authentication.

While HTTPie CLI is free and open source, it also offers a paid tier for businesses, with GUI and team collaboration features, diverging from the core CLI philosophy.

Pros

• Excellent for scripting and automation, sharing commands is as easy as sharing a shell script.
• Completely free and open source, and HTTPie for business is available with GUI.
• Extremely lightweight and fast, optimized for CLI workflows.

Cons

• No built-in team features, collaboration relies heavily on external tools and scripts.
• CLI-only, HTTPie is not suitable for users preferring a GUI.
• HTTPie for business is paid and deviates completely from the core CLI philosophy.

Bruno: The modern open-source API client

Bruno attempts to disrupt the status quo with a powerful manifesto, and a team that’s trying to tackle the exact pain points that make Postman & Hoppscotch hard to work with: vendor lock-in, bloatware, and proprietary cloud-based platforms. Bruno claims to be a developer-first and extensible platform, where ‘platform’ features are non-goals. It is offline-first (yes!), where data isn’t automatically synced to any cloud, and it has native git integration, which simplifies collaboration between developers (since most developers are already familiar with git as a distributed version control and collaboration tool).

Features

Of course, the real picture of Bruno is that it’s still catching up. Its only major drawback is that it just supports HTTP (REST) and GraphQL, with no support for real-time APIs yet.

• A friendly UI for sending requests and inspecting responses.
• Collections are first-class citizens, that help organise requests and documentation for better collaboration and reuse. Requests and documentation are stored as files in Bru Markup, and collections map the folder structure of the project.
• Offline-first, no file is automatically synced to any cloud, and native git integration allows developers to collaborate via git, a distributed version control system.
• Scripting support in JavaScript, for testing and dynamic requests.
• Secrets management with environment variables within the API client.

The killer feature of course is the git-based collaboration, since this enables GitOps for API collections, which means each git branch can have different versions, and these can be merged, or even reviewed via PRs (Pull Requests). Bruno is also completely free & open source.

Pros

• Native git integration is familiar to developers, making version control and collaboration very easy.
• Being free & open source makes it ideal for individual developers and open-source projects.
• Bruno is offline-first, while also being lightweight, fast and responsive. It’s focus on privacy is unparalleled.

Cons

• Native git integration gives non-git users a steeper learning curve, and a moderately difficult experience when collaborating.
• Community support provided, with no paid support plans available.
• Community and ecosystem around Bruno are still growing, since it’s an emergent tool.
• Being offline-first, Bruno doesn’t have any cloud-based features.

Choosing the Right Tool

Choose Bruno if:

• Your team heavily relies on Git for version control.
• You prefer open-source and free tools.
• Offline functionality and data privacy are priorities.
• You want a lightweight and fast API client with GitOps workflow for API collections.

Choose Postman if:

• Your team needs a comprehensive API platform with extensive features across the API lifecycle.
• Cloud-based collaboration and API lifecycle management are essential.
• You require advanced testing, documentation, mocking, and monitoring capabilities.
• You are comfortable with a freemium model and a cloud-centric approach.

Choose Hoppscotch if:

• You need a simple, web-based API client accessible from any browser.
• Real-time collaboration and ease of sharing are important.
• You prefer open-source and free tools with optional cloud features.
• Quick API testing and exploration are primary use cases.

Choose HTTPie (CLI) if:

• You are comfortable with the command line and prefer CLI-based workflows.
• Scripting, automation, and quick ad-hoc requests from the terminal are common tasks.
• Simplicity and readability in the terminal are prioritized.
• GUI is not a requirement, and you prefer a lightweight, fast, and efficient tool for terminal-based API interaction.

Migration Considerations

Bruno & Hoppscotch support Postman collection import

Both Bruno & Hoppscotch make it relatively easy to import Postman collections. It also supports importing environment variables in most cases.

Consider Bru lang for Bruno manual optimisation

Bruno uses Bru, a human readable, plain text markup language that’s git friendly too. This allows us to optimize collections for Bruno’s Git-based workflows if migrating to Bruno.

HTTPie is a different paradigm

Migration to HTTPie from GUI clients means adopting a CLI-based workflow. This could be counter-productive in most situations and potentially require major rewrites.

Conclusion

Developers use API clients to boost productivity, and help us search, test and debug new APIs. Postman holds up as the all-rounder, feature-rich and built for team collaboration over the cloud. Bruno on the other hand offers a refreshing git-centric approach, valuing offline work and data privacy. Hoppscotch is perfect for quick API testing as it’s accessible over the browser. HTTPie is perfect for automation experts, CLI enthusiasts, and those who prioritize speed and shell scripting.

With the variety of APIs and technologies, the API client landscape is widely assorted, with each tool supporting various needs. The tool you pick depends heavily on specific team needs and workflow preferences. Consider factors like collaboration style, budget, API types, privacy needs, and CLI vs. GUI preference.