Dev tools · alternatives · 2026
24 alternatives to Testnizer — The offline API client
Offline, open-source API client. Your data never leaves.
Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes.
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Monitoring for websites, APIs, and cron jobs
2024 · webgazer.io · its alternatives →
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Last time I posted this it didn't garner much interest. There have been lots of improvements and fixes since the last release. Quick list of features: - Workspaces - Tabs - Nested Folders - Lots of context menus - Response history - Plugins - Runs fully in the browser and runs offline if necessary - Chrome and Firefox extension to bypass CORS restrictions - Desktop builds for all platforms - GraphQL support - Import collections exported from Postman and Insomnia - Simple user friendly interface I built this because I love Insomnia but wanted a portable version that I could run in the…
2022 · restfox.dev · its alternatives →
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Hey HN! Aldin here, a helping hand to Voiden (https://voiden.md) Voiden is a free, offline, Git-native API client. Your API definitions, docs, and tests all live together. It came out of years of frustration: cloud sync lock-in, paywalled basics, bloated UIs, and lag on even simple requests. So the team built the opposite: an offline tool with no login, no telemetry, no lock-in. Just markdown and hotkeys. It behaves like code: local files, git branches, no cloud nonsense. Terminal is built-in, so you can commit, diff, and push changes right from the app. Docs stay close to your…
2025 · voiden.md · its alternatives →
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Sparrow▲456The lightest and fastest platform for API testing
2025 · sparrowapp.dev · its alternatives →
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Apicat is the ultimate offline Postman alternative that stores your .http files locally. It’s Git-friendly, open-source, and highly compatible with Postman. Test APIs offline with this powerful free offline API client designed for developers who need a reliable local API testing tool.
2025 · apicat.com · its alternatives →
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Generate, edit, lint & test your API workflow in one place
2025 · app.getelva.ai · its alternatives →
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Clobbr▲444Easy API endpoint load testing without breaking the bank
2023 · clobbr.app · its alternatives →
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- 9MS
2018 · mocktastic.com · its alternatives →
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Beautiful, cross-platform & open-source tools for debugging, testing and building with HTTP(S), on Windows, Linux & Mac.
2019 · httptoolkit.tech · its alternatives →
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Leading Open Source API Development Platform for HTTP, REST, GraphQL, gRPC, SOAP, and WebSockets
2017 · insomnia.rest · its alternatives →
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Your playground for writing custom API security tests
2023 · akto.io · its alternatives →
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Git friendly, offline-only API testing tool
Nov 2025 · hawkclient.com · its alternatives →
- 14DA
This is a project I've been working on since the start of Covid-19. I built an app so that I don't have to put data into online tools like JWT debugger, JSON formatter, URL decoder, etc... https://devutils.app The app works entirely offline and is open-source. I'm selling the pre-built version of the app to earn some revenue for my time. If you want to try the app but can't afford the price or don't have XCode to build the app, drop me an email (my profile), I'll be happy to provide you a free build. I would love to hear all the feedback/suggestions. Thanks!
2020 · its alternatives →
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Hurl, run and test HTTP requests with plain text and curl. Hurl can run fast automated integration tests.
2021 · hurl.dev · its alternatives →
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DevHub▲126Offline applications to support developers' daily tasks
2024 · apps.apple.com · its alternatives →
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2019 · github.com · its alternatives →
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Karate Labs▲115Open-source platform unifying API & UI test automation
2023 · karatelabs.io · its alternatives →
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Terminal API client for HTTP, GraphQL and gRPC. Plain .http files you can diff and version, with workflows, mocks, profiling, tracing, OpenAPI import, SSH tunnels, Kubernetes port-forwards, WebSocket, SSE and a CLI runner. - unkn0wn-root/resterm
2025 · github.com · its alternatives →
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Write, run, and test JavaScript snippets & JSON offline
Aug 2026 · chromewebstore.google.com · its alternatives →
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Mockoon is the easiest and quickest way to run mock REST API servers. No remote deployment, no account required, free, open source and cross-platform.
2017 · mockoon.com · its alternatives →
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Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →