Base64 Encoder / Decoder
Encode and decode text or files to Base64 instantly.
Max file size: 10MB. Files are processed in your browser only.
What is Base64 Encoding?
Base64 is a method of encoding binary data into a text format using only 64 safe ASCII characters (A-Z, a-z, 0-9, +, /, and =). It's commonly used to transmit binary data over text-only channels like email or JSON APIs. This tool lets you instantly encode any text or file to Base64, and decode Base64 strings back to their original form.
How to Use the Base64 Encoder & Decoder
Simply paste your text into the input box and click "Encode to Base64" to convert it to Base64 format. To decode, paste a Base64 string and click "Decode from Base64". The tool also supports file uploads — select a file to encode it to Base64. All processing happens in your browser; your data is never sent to any server.
Common Uses for Base64 Encoding
- Email attachments: Encode binary files for email transmission.
- Data URIs: Embed images and files directly into HTML/CSS using data URLs.
- API requests: Send binary data in JSON payloads that require text-only formats.
- Authentication: Encode credentials for HTTP Basic Authentication.
- Configuration files: Store binary data in text-based config files.
Frequently Asked Questions
Is my data safe?
Yes, completely. All encoding and decoding happens in your browser. Your data never leaves your device and is never stored on our servers.
What file types can I encode?
Any file type can be encoded to Base64. The maximum file size is 10MB. For larger files, consider processing them in batches.
Why does Base64 output look longer than the input?
Base64 encoding increases the size of the data by approximately 33%. This is because Base64 uses 6 bits per character instead of 8 bits per byte.
Can I decode any random text?
Only valid Base64 strings can be decoded. If you try to decode invalid Base64, you'll see an error message. Base64 strings use only A-Z, a-z, 0-9, +, /, and = characters.
Is there a file size limit?
For practical purposes, the tool can handle files up to 10MB. Very large files may be slow to process depending on your browser's memory.
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