DEV-002
Base64 Encoder & Decoder
Base64 represents binary data using 64 printable ASCII characters. It is how binary content travels safely through systems that were designed for text, such as email, JSON fields and data URLs.
- Free
- No signup
- Private · runs locally
How to encode and decode Base64
- Choose the Encode or Decode tab.
- Paste your text or your Base64 string into the input.
- The result appears immediately as you type.
- Copy the output with one click.
What Base64 is for - and what it is not
Base64 is an encoding, not encryption. Anyone can decode it instantly, as this page demonstrates. Never use it to hide passwords, tokens or personal data.
It exists because some channels only reliably carry text. Email attachments, inline images in CSS as data URLs, certificates and binary values inside JSON all rely on it.
The cost is size: encoded output is about 33% larger than the input, because every three bytes become four characters. The trailing = signs are padding that keeps that grouping intact.
This tool handles the full Unicode range correctly, so accented characters and emoji encode and decode without corruption.
Frequently asked questions
Is Base64 encryption?
No. It is a reversible encoding with no key and no secret. It provides no security whatsoever.
Why does my Base64 string end with = signs?
Base64 works in groups of three bytes. When the input length is not a multiple of three, = characters pad the final group.
Why does decoding fail?
Usually the string was truncated, had characters added by line wrapping, or uses URL-safe Base64 where - and _ replace + and /. Check the string is complete and unmodified.