Base64 Encode / Decode
Encode text to Base64 or decode Base64 back to text — UTF-8 safe, in your browser.
🔒 Private by design. This tool runs entirely in your browser — the values you enter never leave your device.
Encode any text to Base64 — the format used to safely carry data in URLs, emails and config files — or switch direction to decode Base64 back into readable text. Everything runs entirely in your browser; nothing is uploaded.
Formula / method
Examples
SGVsbG8gV29ybGQ=
VXRpbEdlYXJz
Hello World
What Base64 encoding does
Base64 turns arbitrary bytes into a safe set of 64 text characters, so binary or awkward data can travel through systems that expect plain text — email, data URLs, JSON fields and config files. It is an encoding, not encryption: it hides nothing, it only reshapes.
When you will reach for it
Common uses include embedding a small image directly in HTML or CSS, storing binary data in a text-only field, and encoding credentials for certain HTTP headers. Encoding adds about a third to the size. To reverse it, use the Base64 Decoder; to learn more, see the What Is Base64 guide.
Where it's used
- Embedding small images or fonts directly in HTML and CSS as data URLs
- Storing binary data inside a JSON, XML, or plain-text database field
- Building HTTP Basic Auth headers, which encode user:password
- Encoding attachments and non-ASCII content in email via MIME
- Passing binary payloads safely through text-only APIs and config files
Real-world examples
- 'Hello World' encodes to SGVsbG8gV29ybGQ=, safe to drop into a JSON string.
- A small PNG icon becomes a data:image/png;base64,... URL embedded straight in a stylesheet.
- The credentials user:pass encode to dXNlcjpwYXNz for an Authorization: Basic header.
A bit of history
The scheme now known as Base64 was first standardized in the Privacy-Enhanced Mail (PEM) specification, RFC 989, in 1987, and became widespread when MIME adopted it to carry attachments in email in the 1990s.
Did you know?
Base64 grows data by about a third, since every 3 bytes become 4 text characters. The trailing = signs you often see are padding that keeps the output aligned to that group of four.
FAQ
Is Base64 encryption?
No. Base64 is an encoding, not encryption — anyone can decode it. It is used to safely represent binary data as text, not to keep data secret.
How do I decode Base64?
Switch the direction to Decode and paste your Base64 (A–Z, a–z, 0–9, +, / and = padding). The tool returns the original UTF-8 text; invalid input is flagged.