Base64 Encoder / Decoder
Encode text to Base64, or decode Base64 back to readable text.
Encoding and decoding happen locally in your browser and are never sent anywhere.
About this tool
Base64 is a way of encoding binary or text data as a string of plain ASCII characters, so it can be safely transmitted or stored anywhere that expects text — inside a URL, a JSON field, an email attachment, or a data: URI for an inline image.
This tool supports full Unicode text (not just basic ASCII) and runs entirely in your browser, so pasted content never leaves your device.
It's worth remembering that Base64 is an encoding, not encryption: it's fully and trivially reversible, so it should never be relied on to protect sensitive or secret data — only to represent it safely as text.
Related tools
Frequently asked questions
- What is Base64 encoding used for?
- Base64 encodes binary or text data into a string of plain ASCII characters (A-Z, a-z, 0-9, + and /), which is commonly used to embed data in URLs, JSON payloads, email attachments (MIME), and data: URIs for images embedded directly in HTML or CSS.
- Is my data sent to a server?
- No — all encoding and decoding happens locally in your browser using standard JavaScript APIs. Nothing you type or paste here is transmitted anywhere.
- Is Base64 encryption or a security measure?
- No. Base64 is an encoding, not encryption — it's fully reversible by anyone with no key required, and is only meant to represent binary data safely as text. It should never be used to protect sensitive information.
- Why does Base64-encoded text look longer than the original?
- Base64 represents every 3 bytes of input as 4 ASCII characters, so encoded text is roughly 33% longer than the original. That overhead is the trade-off for being able to safely represent any binary data as plain text.