Base64 Encoder & Decoder Online – Encode Or Decode Text Free

Base64 is the universal translator that lets binary data and special characters travel safely through systems designed for plain text: emails, URLs, JSON payloads and HTML data URIs all rely on it. Our free Base64 encoder and decoder converts text in both directions instantly, with proper Unicode handling so accented characters, non-Latin scripts and emojis survive the round trip intact. Whether you are decoding a mysterious string from a log file or preparing an encoded value for an API, this tool gives you the answer in one paste.

Quick Answer: Paste plain text and click Encode to get its Base64 form, or paste a Base64 string and click Decode to recover the original text. Unicode and emojis are fully supported both ways.

Free Online Tool

Base64 Encoder / Decoder

Convert text to Base64 and back, with full Unicode support.

Text or Base64

Table of Contents

How to Use the Base64 Encoder / Decoder

Paste the text or Base64 string into the box.
Click Encode to Base64 if your input is normal text, or Decode from Base64 if it is an encoded string.
Read the result in the same box, with a message confirming the conversion and its length.
If decoding fails, the error message tells you the input is not valid Base64 so you can check for truncation.
Copy the converted value with the Copy button for use in your code, email or configuration.

Key Features

Two-way conversion between plain text and Base64 in a single tool.
Correct Unicode handling via UTF-8, unlike naive encoders that break on emojis and accented letters.
Validation with friendly errors when the pasted string is not valid Base64.
Handles long inputs such as encoded certificates, tokens and data payloads.
Fully local processing: sensitive strings, tokens and keys are never uploaded.

Best Practices and Tips

Recognise Base64 at a glance: it uses A–Z, a–z, 0–9, '+' and '/', often ends with one or two '=' padding characters, and its length is a multiple of four.
Base64 grows data by about 33 percent; avoid it for large files when a binary transfer option exists.
Never treat Base64 as encryption. Anyone can decode it instantly with this very tool, so never 'hide' passwords with it.
When embedding in URLs, watch for '+' and '/' characters; use a URL-safe variant or the URL Encoder for query strings.

Common Mistakes to Avoid

Assuming a failed login secret is broken when it is actually Base64-encoded and needs decoding first (or the reverse).
Copying a long encoded string with a line break or missing final characters; even one missing character can make it undecodable.
Encoding text that contains accented characters with a Latin-only tool and corrupting it; always use a Unicode-aware encoder like this one.

Frequently Asked Questions

What is Base64 used for?

Base64 carries binary data through text-only channels. Everyday uses include email attachments (MIME), embedding small images in HTML or CSS as data URIs, transporting tokens and certificates in JSON, and encoding basic credentials in HTTP headers.

Is Base64 a form of encryption?

No. Base64 is an encoding, like writing numbers in a different base. There is no key and no secrecy; anyone can reverse it instantly. For secrecy you need real encryption such as AES, usually combined with proper key management.

Why does encoded text end with '=' signs?

The equals signs are padding. Base64 processes data in groups that produce four characters at a time; padding fills the final group when the input length is not a multiple of three bytes, and tells the decoder exactly where the data ends.

How much bigger does Base64 make data?

Exactly 4 output characters for every 3 input bytes, an increase of about 33 percent, plus possible padding. A 100 KB image becomes roughly 133 KB when Base64-encoded.

Can I encode an image file here?

This tool is for text. For images, use our Image to Base64 Converter, which reads the file and produces a ready-to-use data URI with the correct media type prefix.