Every backend and frontend developer ends up with one app permanently open next to the editor: the API client. It is where you build requests, inspect responses, debug the 401 that only happens on staging, and run the checks before a release. You will spend hundreds of hours in it, so the choice deserves more than a glance at a feature grid.
This guide compares the seven clients developers actually shortlist in 2026: Postman, Insomnia, Bruno, Hoppscotch, Yaak, Thunder Client and our own Apiboo. We make one of the tools on this list, so we kept the criteria objective, checked every competitor claim against its own site in September 2026, and say plainly where each one is the better pick. Prices change often; treat the figures as a snapshot and check the vendor’s pricing page before you buy.
What actually matters in a REST API client
Feature checklists all blur together. In practice, six questions separate the tools:
- Protocols: REST is table stakes. Do you also get GraphQL, WebSocket, SSE and gRPC when a project needs them, and are they on the free plan?
- Where your data lives: on your machine, in a vendor’s cloud, or in Git? Can you use the app without an account?
- Auth depth: OAuth 2.0 with PKCE, AWS Signature v4 and mTLS client certificates are where lightweight clients tap out.
- Team workflow: how do two people share a collection — cloud sync, Git and pull requests, or both?
- Licence and price: open source, free for personal use only, or per user per month? What does a five-person team pay?
- Everything around the client: mocks, docs, the database, the servers and the conversation about the work — built in, or five more apps?
The seven clients at a glance (September 2026)
One line per tool: how it runs, where your collections live, and what it costs.
- Postman — desktop and web platform; cloud workspaces, plus Native Git in v12 for team workspaces; Free is limited to one user since March 2026, Solo $9/month, Team $19/user/month billed annually.
- Insomnia (Kong) — desktop app, Apache-2.0; per-project Local Vault, end-to-end encrypted Cloud Sync or Git Sync; Essentials $0 (Git Sync for up to 3 users), Pro $12/user/month.
- Bruno — desktop app, MIT; offline only, collections as plain-text files in your repo; open-source edition free, Pro $6 and Ultimate $11 per user/month billed annually.
- Hoppscotch — browser-first with a desktop app, MIT, self-hostable; free cloud tier, Organization $6/user/month.
- Yaak — desktop app by Insomnia’s original creator, MIT source; free for personal use, a licence for work use ($79/year individual, $149/user/year business).
- Thunder Client — VS Code extension; free tier without collections since August 2025; Starter $3, Business $7, Enterprise $16 per user/month billed annually.
- Apiboo — local-first desktop app for Windows, macOS and Linux; every local tool free with no account; sync and team workspaces from Pro.
Postman — the platform, and the heaviest
Postman is the incumbent for a reason: the broadest protocol list (HTTP, GraphQL, gRPC, WebSocket, Socket.IO, MQTT, SOAP, SSE over HTTP), monitoring, governance, a public API network and a huge community. If you publish public APIs at scale, its ecosystem is unmatched, and v12 finally put collections on disk with Native Git.
The trade-offs are just as well known. The Scratch Pad was retired in 2023, and signed out you now get a lightweight client for quick requests rather than your collections. Since the March 2026 plan change the Free plan covers a single user, so any shared workspace means the Team plan per seat. Newman does not read the v3 collection format that Native Git uses; Postman points CI users to the Postman CLI instead.
Insomnia — the focused designer’s client
Kong’s Insomnia remains a clean, capable client with genuine strengths: a design-first workflow around OpenAPI, REST, GraphQL, gRPC, WebSocket and SSE, pre-request and after-response scripts, a collection runner, and storage you choose per project: Local Vault, end-to-end encrypted Cloud Sync, or Git Sync.
Its history is the caveat. Insomnia 8.0 made sign-in mandatory in September 2023, and local projects came back in 8.3 a few weeks later after a loud backlash. According to its README, everything beyond the account-free Scratch Pad still expects a free account. It is a client, full stop: no boards, no database tooling.
Bruno — Git-native and open source
Bruno stores collections as plain-text files in your repo (YAML in the OpenCollection format by default since version 3.1, with the older .bru format still supported), works entirely offline, and states it will never add cloud sync. Its core is MIT-licensed. It now covers REST, GraphQL, gRPC, WebSocket, SSE and SOAP, and has added mock servers and a CLI for CI.
The Git-only model is also its ceiling for some teams: environment changes are commits, secrets are .env files unless you pay for the Ultimate tier’s secret-manager integrations, and collaboration routes through pull requests. The Git UI itself (clone, diff, branches, conflicts) is an Ultimate feature.
Hoppscotch — the browser-first option
Hoppscotch runs in a browser tab, is MIT-licensed and can be self-hosted, and it has grown into a real client: REST, GraphQL, WebSocket, SSE, Socket.IO and MQTT, pre-request scripts and tests, a collection runner with iterations, a CLI, and since October 2025 mock servers. As a zero-install client, or a self-hosted tool inside a locked-down organisation, it is excellent.
In the browser, CORS, localhost and client certificates need the browser extension or the local Hoppscotch Agent; its desktop app avoids that. gRPC is not on its protocol list.
Yaak — the fast, local, opinionated newcomer
Yaak is built by Gregory Schier, who created Insomnia, and it shows: a quick, native-feeling app (Tauri and Rust) with REST, GraphQL, gRPC, WebSocket and SSE, no account, no telemetry, secrets encrypted in the operating system’s keychain, a plugin system, and workspaces you can mirror to a folder for Git. It imports Postman, Insomnia, OpenAPI, Swagger and cURL.
Its source has been MIT-licensed since September 2024, but the signed builds need a licence when you use Yaak at work: $79 a year (or $399 lifetime) for an individual, $149 per user per year for a business. Personal use is free. Teams typically share workspaces through Git.
Thunder Client — the editor sidebar
Thunder Client lives inside VS Code (and, on paid plans, JetBrains IDEs). For firing the endpoint you just wrote without leaving the editor, nothing has less friction, and its scriptless GUI tests are pleasant for simple assertions.
Its free tier has shrunk in stages: since August 2025 it has no collections at all, and WebSocket, SSE and gRPC are listed on the paid plans. Collections, Git sync and CI runs start at the Starter plan. For anything past quick REST calls, you are choosing a paid tool.
Apiboo — the all-in-one, local-first app
Apiboo is our entry, and its bet is different: keep the local-first privacy Bruno and Yaak users care about, match the client features Postman users rely on, and bundle the tools around the API work that every other client leaves to separate apps.
The client: REST, GraphQL, WebSocket, SSE and gRPC; OAuth 2.0 (authorization code with PKCE, client credentials), AWS Signature v4 and mTLS client certificates; variables and environments; pre-request and post-response scripts with Apiboo’s boo.* API plus Postman’s pm.*, Bruno’s bru.* and Hoppscotch’s pw.*, so most imported scripts run unchanged; a collection runner; a local mock server; code generation in nine languages; import from Postman, Insomnia, Bruno (whole collections), Hoppscotch, OpenAPI/Swagger, HAR and pasted cURL. Around it: a database manager for PostgreSQL, MySQL and SQLite, a terminal with SSH and split panes for coding agents, FTP/SFTP, a local mail catcher, task boards, documents, a calendar, team chat, a vault for passwords and keys, and a built-in MCP server so AI agents can work with your data with your permission.
Every local tool is free with no account, and the app works offline. Pro adds unlimited sync, cloud workspaces, vault sync, cloud mocks and one team of up to three people; the Team plan adds shared team workspaces for larger teams. The honest caveats: Apiboo is the youngest tool here and a commercial product, not open source; its runner has no iterations or data files yet, and gRPC covers unary and server-streaming calls only. If you need a decade-deep ecosystem or an OSI licence, look above.
Decision matrix
Find your strongest requirement; the tool on the right is the one we would shortlist first.
- You publish public APIs and need monitoring, governance and a public network → Postman.
- Design-first OpenAPI work, or you run Kong’s gateway → Insomnia.
- Open source is non-negotiable and collections must be reviewed in pull requests → Bruno.
- Zero install, or self-hosted inside the company network → Hoppscotch.
- A fast, local, account-free client for personal projects, with a fair paid licence for work → Yaak.
- You only poke a few REST endpoints while coding and never leave VS Code → Thunder Client.
- Offline and account-free, with the free plan covering all five protocols, and you also want the database, SSH, boards and chat in the same app → Apiboo.
- A team of five on a small budget → compare Insomnia Essentials, Bruno with Git, and Apiboo Pro or Team against Postman Team’s per-seat price for your actual headcount.
Try the migration, not the marketing
Every serious client now imports the others’ formats. The cheapest way to decide is to import your real collection into two candidates and run your actual workflow for a day each. Marketing pages, this one included, are no substitute for your own staging environment returning a 403 at 5 pm. If Postman is where you are coming from, our longer guide at apiboo.com/blog/postman-alternatives and the side-by-side at apiboo.com/compare/postman go deeper.
Try it with your own work
Export a collection from the tool you use today (Postman, Insomnia, Bruno, Hoppscotch, an OpenAPI spec or a HAR file), or take your Bruno collection folder as it is, and drop it on Apiboo’s Import collection dialog; the preview lists anything that does not carry over before you commit.
Download Apiboo for Windows, macOS or Linux at apiboo.com/download. It is free to start, with no card and no account: every tool runs on your own machine, and you only sign in when you want sync or a team.