2026-09-01

18 Free Developer Tools That Run Entirely in Your Browser

Most "online tool" sites are one tool per domain, each with its own ads, its own upload-to-a-server round trip, and its own account wall eventually. iLoveDevTools is the opposite bet: one place, 18 tools, everything processed client-side in your browser tab — nothing you paste is ever transmitted anywhere. No signup, no ads, no server round-trip for your data.

Here's the full list, grouped the same way the site groups them.

File Utilities

• PDF to Base64 — Upload a PDF and convert it into a Base64-encoded string for easy sharing or embedding.
• Base64 to PDF — Convert a Base64 string back into a downloadable PDF file.

Encoding & Hashing

• Base64 Encoder — Encode data into Base64, or decode a Base64 string back to its original form.
• URL Encoder — Encode and decode URI components so they're safe to use in URLs.
• Hash Generator — Generate cryptographic hashes (SHA-256, SHA-512, and others) from text.
• UUID Generator — Generate universally unique identifiers with a single click.

Web & API

• JSON Tools — Format, validate, and minify JSON, with automatic fixes for common issues like single quotes and trailing commas.
• JWT Debugger — Decode and inspect a JSON Web Token's header, payload, and signature.
• SQL Formatter — Turn a dense, minified SQL query into consistently indented, readable output.
• cURL Converter — Convert cURL commands into native code snippets (JavaScript, Python, and more).

Text & Data

• Regex Tester — Test and debug regular expressions in real time, with syntax highlighting and match results.
• List Utilities — Sort, deduplicate, and count distinct entries in a list.
• Array Generator — Turn a plain list into an array literal for your language of choice.
• Markdown Previewer — Write Markdown and see a live, rendered HTML preview side-by-side.
• Code Diff Viewer — Compare two blocks of text or code and see a visual diff.

Converters

• Timestamp Converter — Convert between Unix timestamps and human-readable dates.
• Color Converter — Convert colors between HEX, RGB, and HSL, with a built-in picker.
• Data Format Converter — Convert data between JSON, YAML, and CSV for config files and data exchange.

Why client-side matters

Every tool above runs its transform using your browser's own JavaScript engine — parsing, formatting, hashing, converting. Nothing you paste is uploaded anywhere first. For things like JWTs or config files that can carry real, sensitive data, that's not a minor detail; it's the difference between "this tool happened to not misuse my data" and "this tool architecturally cannot."

That's the whole premise of iLoveDevTools — small, sharp, boring-in-a-good-way utilities, all in one place, none of them capable of seeing what you paste into them.

Try iLoveDevTools