Is this Base64 tool free?

Yes, completely free with no account or subscription required.

Does it upload my data to a server?

No. All encoding and decoding happens locally in your browser. Nothing is ever sent to any server.

Does it work offline?

Yes. Once the page is loaded, it works without an internet connection.

Does it support Korean and other non-ASCII characters?

Yes. The tool uses UTF-8 safe encoding, so Korean, Japanese, emoji, and any Unicode text is fully supported.

What is URL-safe Base64 and when should I use it?

URL-safe Base64 replaces + with - and / with _ and removes padding (=), making the output safe to include directly in URLs or filenames without percent-encoding. Use it for JWT tokens, URL parameters, or file naming schemes.

Is Base64 a form of encryption?

No, and treating it as one is a real security mistake. Base64 is a reversible encoding with no key involved - anyone can decode it in a second, including with this page. It exists to carry binary data safely through text-only channels such as email headers, not to hide anything.

Why does encoding make my data bigger?

Base64 packs every three bytes into four printable characters, so the output is about a third larger than the input, plus padding. That overhead is the price of being safe to paste anywhere, and it is why embedding large images directly into HTML or CSS as Base64 makes the page heavier than linking the file.

🔐 Base64 Encoder / Decoder

Instantly encode text to Base64 or decode Base64 back to plain text — free, runs entirely in your browser, no file upload required, and works offline.

Text

Base64

Private by design. This tool runs entirely in your browser — nothing you enter is uploaded or stored, and it works offline.

About

This tool converts text to and from Base64 encoding directly in your browser using the Web Crypto APIs — your data never leaves your device. It supports full UTF-8 input including Korean, Japanese, and emoji, plus a URL-safe mode that replaces + and / with - and _ and strips padding for use in URLs and filenames. Your last input is automatically saved in localStorage so you can pick up where you left off.

How to use

Paste or type your plain text into the top Text panel.
(Optional) Check 'URL-safe' if you need the result safe for use in URLs or filenames.
Click 'Encode ↓' to convert text to Base64; the result appears in the Base64 panel below.
To decode, paste a Base64 string into the bottom panel and click 'Decode ↑'.
Use the Copy buttons to copy either result to your clipboard.

FAQ

Is this Base64 tool free?: Yes, completely free with no account or subscription required.
Does it upload my data to a server?: No. All encoding and decoding happens locally in your browser. Nothing is ever sent to any server.
Does it work offline?: Yes. Once the page is loaded, it works without an internet connection.
Does it support Korean and other non-ASCII characters?: Yes. The tool uses UTF-8 safe encoding, so Korean, Japanese, emoji, and any Unicode text is fully supported.
What is URL-safe Base64 and when should I use it?: URL-safe Base64 replaces + with - and / with _ and removes padding (=), making the output safe to include directly in URLs or filenames without percent-encoding. Use it for JWT tokens, URL parameters, or file naming schemes.
Is Base64 a form of encryption?: No, and treating it as one is a real security mistake. Base64 is a reversible encoding with no key involved - anyone can decode it in a second, including with this page. It exists to carry binary data safely through text-only channels such as email headers, not to hide anything.
Why does encoding make my data bigger?: Base64 packs every three bytes into four printable characters, so the output is about a third larger than the input, plus padding. That overhead is the price of being safe to paste anywhere, and it is why embedding large images directly into HTML or CSS as Base64 makes the page heavier than linking the file.