- Choose a mode. Text works on whatever you type or paste. File works on a chosen file instead.
- Type your content and press Encode, or paste a Base64 string and press Decode.
- Copy the result, or download it in file mode.
Base64 turns binary or text data into a printable ASCII string, which is widely used for embedding images in HTML and CSS, carrying binary data in JSON, and encoding simple authentication headers.
All processing runs locally in your browser. Nothing you encode or decode is ever uploaded, so sensitive strings or confidential files can be handled safely. The tool works with standard Base64 that uses letters, digits, plus, slash and padding with equals signs.
Tips
Base64 is not encryption — it is just encoding. Anyone can decode the result, so never use it to hide passwords or private data. The encode output is roughly a third larger than the original input, which matters when you embed files into code or email.
For embedding a small image into a web page, File mode plus Encode gives you a data URI you can drop straight into your markup. Remember the encoded string grows as the file grows, so for large files a real hosting URL is usually a better choice than an inline data URI.
Why use it
Developers constantly need to encode or decode Base64 when working with inline assets, API payloads, and encoded configuration values. Doing it in the browser is instant, free and private, with no extensions to install and no files sent to a remote server.
Real-world use cases
- Content production: Transform text for CMS, spreadsheets or translation workflows without manual retyping.
- Data handling: Clean and normalize strings before pasting into code, databases or AI prompts.
- Privacy-sensitive work: Process contracts, notes or personal text that you would never upload to a server.
How it compares
| Tool | Offline | Privacy | Install needed | Cost |
|---|---|---|---|---|
| This tool | Yes | 100% local | No | Free |
| Online server tools | No | Uploaded | No | Free/Ads |
| Desktop apps | Yes | Local | Yes | Paid |
When privacy and instant access matter, a browser-only tool is the most practical choice.
Pro tips
- For large texts, paste in chunks if your device is older. The tool still processes locally but will stay snappier.
- Combine with other tools: convert case, then run text analyzer for frequency, then encrypt if you need to share.
- Use diff mode to proofread translations or AI rewrites side-by-side before publishing.