Focused developer utilities

Browser-Native Developer Tools

For JSON, API testing, regex, and image optimization.

Runs entirely in your browser — no setup, no uploads.

Format JSON instantly Browse developer tools

And more tools

Browse the full useSignal toolset.

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Core developer utilities

Start with the essentials.

Browse JSON formatters, API testing tools, a regex generator, an image optimizer, and focus utilities that open fast and run in the browser.

New in useSignal

Signal Playground

Try small JavaScript and HTML/CSS ideas in one split-view workspace that loads fast.

Open Code Playground

Scroll or use arrows as the featured set grows.

Utility

NEW

Signal Playground

Browser-based code playground for JavaScript snippets and HTML/CSS preview.

Run small snippets without opening a full IDE

Open Code Playground

Utility

NEW

JSON to Form

Turn JSON payloads into editable form UI for prototypes and admin screens.

Generate forms directly from JSON payloads

Generate form from JSON

Utility

NEW

Color System Generator

Generate semantic light/dark design tokens with export-ready developer output.

Preview light and dark token systems

Open Color System Generator

Utility

NEW

Smart Regex Builder

Generate, test, and explain regex patterns instantly in your browser.

Generate regex from examples in seconds

Generate regex pattern

Utility

HOT

API Request Playground

Send API requests, inspect responses, and replay recent calls in your browser.

Speeds up everyday endpoint testing

Open API Request Playground

Utility

HOT

Image Truth

Reduce image size without losing quality. Runs locally — no uploads.

See quality tradeoffs before export

Open Image Truth

Utility

Live

Deep Work

Pomodoro timer with focus insights, streaks, and local session tracking.

Built for calmer focus rituals

Open Deep Work

Module

Live

Reset

Quick stress relief tools for browser-based mental resets.

Open Reset

Utility

NEW

API Mock Generator

Generate success, empty, error, and paginated API responses from sample JSON.

Covers empty, error, and paginated states

Generate mock response

Utility

NEW

JSON Visualizer

Format and visualize JSON, clean messy data, and inspect large payloads.

Format, minify, and clean JSON instantly

Format JSON instantly

Browser-native tools for fast developer workflows

useSignal keeps practical developer utilities close to the browser: local-first JSON tools, API testing, image optimization, design token generation, regex building, focus sessions, and quick reset tools.

JavaScript playground & HTML/CSS editor Smart Regex Builder JSON to Form JSON Visualizer API Mock Generator Color System Generator API Request Playground Image Truth Deep Work Reset

Why useSignal exists

A cleaner home for focused developer utilities.

useSignal brings useful browser-native tools into one place so developers can move faster with less clutter. Each utility is quick to open, easy to trust, and narrow enough to stay useful.

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