Base64 Encoder / Decoder
Free online tool · runs in your browser
Encode or decode Base64 text.
Quick tutorial
- 1Enter text.
- 2Choose Encode or Decode.
- 3Use Swap to move output back to input.
Free online base64 encoder / decoder
Encode and decode Base64 online with UTF-8 support. Convert text to Base64 for data URLs, basic auth headers, or email-safe payloads, then decode it back. Swap output into input to reverse a conversion quickly. Invalid Base64 shows a clear error instead of garbage text. All encoding stays in the browser. Read our guide explaining why Base64 is not encryption before you treat opaque strings as secrets.
Documentation last reviewed .
Encoding is not encryption
Base64 is reversible without a key. Use it for transport compatibility, not for hiding secrets. For confidentiality use real encryption; for integrity use cryptographic hashes. Our Base64 tool supports UTF-8 text encode and decode entirely in your browser.
Read the guide “Base64 Encoding Is Not Encryption” for clearer boundaries between encoding, hashing, and encryption — and when each belongs in your stack.
How to use Base64 Encoder / Decoder
- Enter text.
- Choose Encode or Decode.
- Use Swap to move output back to input.
Limitations
- Invalid Base64 input will show a clear error.
Example
Input
Hello
Output
SGVsbG8=
FAQ
Frequently Asked Questions
Does this Base64 tool support Unicode?
Yes. Text is encoded and decoded as UTF-8, so emoji and non-Latin characters work.
Is Base64 encryption?
No. Base64 is encoding, not encryption. Anyone can decode it in one step. Use real encryption for confidentiality.
Can I use this for passwords?
No. Do not store or “protect” passwords with Base64. Use a password hashing algorithm such as Argon2 or bcrypt in your application.
Does encode/decode leave my device?
No. Conversion runs locally in your browser.
Does it support Unicode?
Yes, UTF-8 text is handled correctly.
Is Base64 Encoder / Decoder free to use?
Yes. Base64 Encoder / Decoder on ShadowReference is free, with no account, no watermarks, and no server-side processing.
Does this tool send my data to a server?
No. All processing happens locally in your browser. Your input never leaves your device.
Related guides
Deeper reading on private, browser-based workflows for base64 encoder / decoder and related tools.
- Base64 Encoding Is Not Encryption — Clear explanation of Base64 vs encryption, when to encode or decode, and how to use a private Base64 tool for UTF-8 text.
- Why Private Browser Developer Tools Matter — Why ShadowReference runs every tool in your browser, what “no upload” really means, and how that helps day-to-day engineering work.