Base64 ↔ Text Converter
Free online tool to encode and decode Base64 instantly. Perfect for encoding binary data, embedding images, handling API tokens, and working with data URIs. Supports standard and URL-safe Base64 variants.
File will be read as binary and encoded to Base64
How to Use the Base64 Converter
- 1.Choose your conversion direction (Text → Base64 or Base64 → Text)
- 2.Enter your text or Base64 string, or upload a file to encode
- 3.Toggle "URL-Safe Base64" if you need to use the encoded data in URLs
- 4.The conversion happens instantly - no need to click a button
- 5.Copy, download, or share your results
What is Base64 Encoding?
Base64 is a binary-to-text encoding scheme that represents binary data in an ASCII string format. It's commonly used to encode data that needs to be stored and transferred over media designed to deal with text.
The encoding uses 64 different characters (A-Z, a-z, 0-9, +, /) to represent binary data, making it safe to transmit through systems that only support text.
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Common Use Cases:
- Embedding images in HTML/CSS (data URIs)
- Encoding binary attachments in email (MIME)
- Storing binary data in JSON or XML
- API authentication tokens (JWT, Basic Auth)
- Encoding file uploads in web forms
- Database storage of binary data
Standard vs URL-Safe Base64
| Type | Character 62 | Character 63 | Padding |
|---|---|---|---|
| Standard | + | / | = |
| URL-Safe | - | _ | Optional |
When to use URL-Safe Base64: Use URL-safe encoding when the Base64 string will be part of a URL (query parameter, path component) or filename, as the standard + and / characters have special meanings in URLs.
Frequently Asked Questions
Is Base64 encryption?
No, Base64 is an encoding scheme, not encryption. Anyone can decode Base64 - it's reversible without a key. Never use Base64 alone to protect sensitive data.
Why does Base64 increase file size?
Base64 encoding increases data size by approximately 33% because it represents every 3 bytes of binary data with 4 ASCII characters. This is the overhead for making binary data text-safe.
Can I encode files with this tool?
Yes! Use the file upload input in "Text → Base64" mode. The file will be read as binary and converted to Base64. This works for any file type (images, PDFs, documents, etc.).
What's the maximum file size I can encode?
Since all processing happens in your browser, the limit depends on your device's memory. For best performance, keep files under 10MB. Very large files may cause the page to slow down or crash.
Is my data safe?
Yes! All conversions happen locally in your browser using JavaScript. Your data never leaves your device and is never sent to any server.
Important Disclaimer
This Base64 converter is provided "as-is" for informational and development purposes only. Base64 is NOT encryption - it's easily reversible. Never use Base64 alone to protect passwords, API keys, or sensitive information. Always verify critical encodings independently before use in production systems. We make no warranties about the accuracy or reliability of conversions.