Free Developer Tools

Everyday utilities for developers — format JSON, encode Base64 and URLs, generate hashes and UUIDs, convert timestamps and colors. Fast, free and private to your browser.

The small dev utilities you reach for daily

Clean up an API response with the JSON Formatter, convert data with Base64 Encode/Decode and URL Encode/Decode, and create secure fingerprints with the Hash Generator (SHA-1, SHA-256, SHA-384, SHA-512).

Need a unique key? The UUID Generator makes random v4 identifiers in bulk. Decode log times with the Unix Timestamp Converter, translate a color across HEX, RGB and HSL, or drop in placeholder copy from the Lorem Ipsum Generator. Each tool runs locally with native browser APIs, so your data never leaves your device.

Frequently asked questions

What developer tools does ToolsKaro offer?

A JSON formatter and validator, Base64 encode/decode, URL encode/decode, a SHA hash generator (SHA-1/256/384/512), a UUID v4 generator, a Unix timestamp converter and a HEX/RGB/HSL color converter — all free and in your browser.

Are these developer tools private?

Yes. Every tool runs entirely in your browser using native APIs like JSON, Web Crypto and crypto.randomUUID(), so the data you paste — payloads, tokens, secrets — is never uploaded to a server.

Do I need to sign up or install anything?

No. There is nothing to install and no account to create. Open a tool and use it instantly on any device.

Why use these instead of a desktop app?

They load instantly, work on any device including your phone, keep your data on your machine, and are completely free with no limits or watermarks.

Explore more free tools

Every ToolsKaro tool is free, needs no sign-up and runs entirely in your browser.

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