DEV3 Free Base64 Encode and Decode — Source Code (React + Tailwind)

Source code of the DEV3 Base64 Encode and Decode, Base64 encoding and decoding with correct UTF-8 handling, URL-safe output, padding control, data URIs and file conversion, all in the browser.

Free download: sign in to any DEV3 account and click Download ZIP. Try it live: https://dev3.tech/tools/base64-encode-decode shows the finished tool running.

What is in the download

• A standalone Vite + React + TypeScript + Tailwind CSS project: src/tool holds the tool, shared pieces sit beside it
• package.json with exact versions plus a lockfile, so npm ci works
• README.md (run, build, embed in Next.js or plain React) and an MIT LICENSE

What the code does

• Text encode/decode that survives non-Latin characters
• Standard and URL-safe alphabets, optional padding
• File to Base64 / data URI and back to a downloadable file
• MIME sniffing for decoded bytes

Tech stack

React 19, TypeScript, Vite, Tailwind CSS 4.

Install and customise

The How to install and How to use tabs list the steps. In short: unzip, npm ci, npm run dev, then copy the tool folder into your own app if you want to embed it.

Good to know

• A browser-only tool: there is no backend or database in the code.