Base64 Encoder & Decoder - Encode/Decode Base64 Online Free
Free online Base64 encoder and decoder. Convert text to Base64 and back instantly in your browser. Supports Unicode characters. No data uploaded.
What is Base64 Encoder?
Base64 is a binary-to-text encoding scheme that converts binary data into a text format using 64 printable ASCII characters (A-Z, a-z, 0-9, +, and /). This Base64 Encoder & Decoder tool lets you instantly convert text to Base64 encoding and decode Base64 strings back to readable text. Base64 is commonly used in email attachments (MIME), embedding images in HTML/CSS as data URIs, encoding API authentication tokens, and storing binary data in JSON or XML. This tool processes everything in your browser — no data is ever sent to a server.
How to Use
- Select 'Encode' to convert text to Base64, or 'Decode' to convert Base64 back to text.
- Type or paste your input in the left area.
- The result appears instantly on the right. Click 'Copy' to copy it.
Features
- Instant encoding and decoding with real-time output
- Full Unicode support — handles emoji, Chinese, Arabic, and all UTF-8 text
- Switch between encode and decode modes with one click
- Copy output to clipboard instantly
- 100% client-side — your data never leaves your browser
- No file size limits beyond your browser's memory
Frequently Asked Questions
Is Base64 the same as encryption?▾
No. Base64 is an encoding scheme, not encryption. Anyone can decode Base64 text without a key. It is designed for data transport, not security. Never use Base64 to protect sensitive data.
Why is the Base64 output larger than the input?▾
Base64 encoding increases data size by approximately 33%. Every 3 bytes of input become 4 characters of Base64 output. This overhead is the trade-off for representing binary data as text.
What is Base64 used for?▾
Common uses include email attachments (MIME encoding), embedding images in HTML/CSS (data URIs), encoding authentication tokens (Basic Auth headers), and storing binary data in JSON or XML formats.
Does this tool support URL-safe Base64?▾
This tool uses standard Base64 encoding. URL-safe Base64 replaces + with - and / with _ to avoid URL encoding issues. You can manually replace these characters in the output if needed.