Base64 Encoder / Decoder
Encode text to Base64 (MIME) or decode Base64 back to plain text. Base64 lets you safely transmit binary data over text-only channels like email or URLs.
Frequently Asked Questions
What is Base64 encoding?
Base64 is a binary-to-text encoding scheme that represents binary data using 64 ASCII characters (A–Z, a–z, 0–9, +, /). The most common implementation is MIME (Multi-Purpose Internet Mail Extensions), used to transmit attachments via SMTP email. Encoding data in Base64 increases its size by roughly 33%.
When should I use Base64 encoding?
Use Base64 whenever you need to embed binary data in a text-only context — email attachments, data URIs in HTML/CSS, JSON payloads, HTTP headers, or storing binary data in XML or text-based configuration files.
Is Base64 encryption?
No. Base64 is an encoding scheme, not encryption. It does not provide any security or confidentiality. Anyone can decode Base64 text back to its original form. For security, use proper encryption algorithms like AES or RSA.
Why does Base64 increase data size?
Base64 represents every 3 bytes of input as 4 ASCII characters, resulting in approximately 33% size increase. This overhead is the trade-off for being able to safely transmit binary data through text-only channels.