Base64 Encoder/Decoder
Encode and decode Base64 strings instantly
Frequently Asked Questions
What is Base64?
Base64 converts binary data to ASCII text using 64 characters. Used in email attachments and data URIs.
Is Base64 encryption?
No. Base64 is encoding, not encryption. Anyone can decode it without a key.
Why use Base64?
To transmit binary through text-only channels like email, embed images in HTML/CSS, or include binary in JSON/XML.
How much larger does data become when Base64 encoded?
Base64 encoding increases data size by approximately 33%. Every 3 bytes of input become 4 bytes of Base64 output. This overhead is the tradeoff for safe text-based transmission of binary data.
What is the difference between Base64 and Base64URL encoding?
Standard Base64 uses + and / characters which are special in URLs. Base64URL replaces them with - and _ to make the output safe for use in URLs and filenames without additional encoding.
What is Base64?
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 or transferred over media designed to handle text.
Base64 encoding increases the data size by approximately 33%.
Common Use Cases
Email Attachments: MIME encoding for email attachments.
Data URLs: Embedding images directly in HTML/CSS.
API Data: Transmitting binary data in JSON.
Authentication: HTTP Basic Authentication headers.