Base64 Encode / Decode
Encodes UTF-8 text to standard base64 and decodes standard base64 back to UTF-8 in the browser. This is encoding, not encryption, and not a file vault. Paste is enough; nothing is uploaded.
Base64 encode / decode
Client-side only. Base64 is encoding, not encryption. This is not a file vault and not a secret store. Paste is enough—no file upload. Nothing is sent to a server.
How to use
- Choose Encode (UTF-8 text → standard base64) or Decode (standard base64 → UTF-8 text). Both live on this page.
- Paste text or base64. Read the result as text and copy it on this device. Invalid base64 fails closed.
- Nothing is sent to a server. Refreshing the page clears the form. This is not encryption and not a file vault.
Results
Paste text to encode to standard base64.
Runs in your browser. Nothing is uploaded.
Frequently asked questions
Is this the page for base64 encode / decode online?
Yes. This one URL, /base64-encode-decode-online/, is the hub for base64 encode / decode online, base64 decode online, and base64 encoder online. There is no /base64-decode-online/, /base64-encoder-online/, /base64-encode-decode/, or /review/base64-encode-decode-online/ page. Encode and decode both run here.
Is base64 encryption?
No. Base64 is encoding, not encryption. Anyone can decode the output. This page is not a secret store, not a file vault, and not a way to hide passwords. Paste text; do not treat the result as protected.
What does encode and decode do here?
Encode turns UTF-8 text into standard base64 (A–Z, a–z, 0–9, +, /) with = padding. Decode turns that standard base64 back into UTF-8 text. Decode strips whitespace first so wrapped lines still work. This page does not emit base64url.
What happens if the base64 is invalid?
Invalid alphabet, missing or extra = padding, leftover padding bits, or bytes that are not valid UTF-8 all fail closed with an error. The page does not skip junk or guess a fix. Empty or whitespace-only paste also fails closed.
Is this a file vault? Do I need to upload a file?
No. This is not a file vault. Paste is enough. There is no required file upload, no account, and nothing is stored. Encoding and decoding run in your browser.
Is my text sent to a server?
No. Encode and decode run in your browser. The paste never leaves the browser. There is no signup, and Tallymill does not save what you enter. Refreshing the page clears the form.
Is there a size limit?
Yes. Input larger than 100KB (100 × 1024 UTF-8 bytes) is rejected. Empty or whitespace-only input also fails closed. Nothing is sent to a server either way.