API Playground

Test APIs & webhooks instantly. No signup, no install.

What it does

Most API tools make you install software, create an account, and share tokens before you can send a single request. API Playground flips that. Open your browser, paste a URL, hit send — done. Full HTTP support, webhook testing for Make.com & Zapier, request history, environment variables, and a beautiful JSON response inspector. 100% free, forever. No hidden plans, no upsells.

Does the same job

all alternatives →

Hello API2024 · ▲187
Turn your boring API docs into an interactive playground
Webhook Catcher2025 · ▲105
Create instant disposable Webhooks to inspect & respond fast
API_TESTER2025 · ▲249
Test your APIs right from the macOS menu bar
Webhooks by Zapier2018 · ▲163
Move Your Data Instantly With Webhooks
IM
I made an online Webhook Tester2024 · webhook.cool · ▲43
Hi HN! Last year, I built LocalCan app in which you can develop apps using .local domains and Public URLs. Although it allows for testing webhooks too, I wanted to give back and create a free online tool specifically for that purpose! And so, I've made Webhook.cool Simply use your unique webhook URL to send any webhook to it from services like Shopify, Slack, Mailchimp, Trello, GitHub, PayPal, Discord, and Jira. Give it a try and let me know how if you have any feedback.
Postkit 2.02019 · ▲129
Codepen for mock APIs

More dev tools this month

the category →

Dograh▲592
The open source VAPI alternative
Dev tools · 25d ago · dograh.com
Meridian▲530
Don't let your work go unnoticed. Get promoted!
Dev tools · 20d ago · meridiona.com
x1▲516
Lovable for iPhone apps go from idea to App Store
Dev tools · 11d ago · x1.new
Computable GPU Index (CGI)▲423
The first open-source price index for GPU compute
Dev tools · 10d ago · getcomputable.com
Open-Source eInk Bike Computer▲406
OpenTrailPaper is open-source bike computer firmware for the LilyGO T5S3 4.7" E-Paper PRO. It supports offline maps, GPX routes, FIT recording and Bluetooth sensors.
Dev tools · 2d ago · opentrailpaper.com
The GTM Co-Founder▲402
Open-source GTM skills for technical founders
Dev tools · 29d ago · gtmcofounder.com

Launched alongside, April 2026

the whole month →

Brila▲1,367
One-page websites from real Google Maps reviews
AI · Apr 2026 · brila.ai
AG
A game where you build a GPU▲964
Thought the resources for GPU arch were lacking, so here we are
Life & fun · Apr 2026 · jaso1024.com
IB
I built a tiny LLM to demystify how language models work▲915
Built a ~9M param LLM from scratch to understand how they actually work. Vanilla transformer, 60K synthetic conversations, ~130 lines of PyTorch. Trains in 5 min on a free Colab T4. The fish thinks the meaning of life is food. Fork it and swap the personality for your own character.
AI · Apr 2026 · github.com
Fathom 3.0▲803
AI meeting notes: now bot-free, in ChatGPT & Claude + more
AI · Apr 2026 · fathom.ai
BC
Brutalist Concrete Laptop Stand (2024)▲786
Life & fun · Apr 2026 · sam-burns.com
IB
I built a frontpage for personal blogs▲783
With social media and now AI, its important to keep the indie web alive. There are many people who write frequently. Blogosphere tries to highlight them by fetching the recent posts from personal blogs across many categories. There are two versions: Minimal (HN-inspired, fast, static): https://text.blogosphere.app/ Non-minimal: https://blogosphere.app/ If you don't find your blog (or your favorite ones), please add them. I will review and approve it.
AI · Apr 2026 · text.blogosphere.app