What is Base64 encoding?

Base64 is a way of representing binary data using only 64 printable ASCII characters (A–Z, a–z, 0–9, + and /). It lets you safely transmit or store data — like images, files, or text with special characters — in systems that only reliably handle plain text, such as URLs, JSON, XML, or email.

How do I encode text to Base64?

Paste or type your text into the input box on the left with "Encode" selected. The Base64 result appears instantly on the right thanks to live mode. Click "Copy" to copy it to your clipboard.

How do I decode a Base64 string?

Switch to "Decode", paste your Base64 string into the input box, and the original text appears on the right. If the string is not valid Base64, you will see a clear error message.

Is this Base64 tool safe and private?

Yes. All encoding and decoding happens entirely in your browser using JavaScript — your data is never uploaded to a server. This makes it safe to use even with sensitive text.

What is URL-safe Base64?

URL-safe Base64 replaces the "+" and "/" characters with "-" and "_" so the result can be used in URLs and filenames without additional escaping. Enable the "URL-safe variant" option before encoding.

Does Base64 encryption keep my data secure?

No. Base64 is an encoding, not encryption — anyone can decode it. Use it for safe transport and storage of data, not to protect secrets. For confidentiality you need real encryption.

How to Decode Base64 — Online, JavaScript, Python & CLI

Base64 is a way to represent binary data using 64 printable characters. Decoding reverses that: it turns a Base64 string back into the original text or bytes. Base64 is an encoding, not encryption — anyone can decode it, so never use it to hide secrets.

The quickest way is the free Base64 decoder — paste, get the result, everything runs in your browser. Below are code methods too.

Decode Base64 online (no install)

Open the Base64 tool and select Decode.
Paste your Base64 string into the input box.
The decoded text appears instantly on the right — click Copy.

Decode Base64 in JavaScript

// Browser (ASCII)
const text = atob("SGVsbG8h");            // "Hello!"

// Browser, UTF-8 safe (emoji, accents)
const bytes = Uint8Array.from(atob(b64), c => c.charCodeAt(0));
const text2 = new TextDecoder().decode(bytes);

// Node.js
const text3 = Buffer.from(b64, "base64").toString("utf8");

Decode Base64 in Python

import base64

text = base64.b64decode("SGVsbG8h").decode("utf-8")   # "Hello!"

Decode Base64 on the command line

echo "SGVsbG8h" | base64 --decode    # Linux
echo "SGVsbG8h" | base64 -D          # macOS

Common Base64 decoding errors

Invalid character: strip stray spaces and line breaks before decoding.
Wrong padding: valid Base64 length is a multiple of 4, padded with =.
It is URL-safe Base64: if the string contains - or _, it uses the URL-safe alphabet — see URL-safe Base64 explained.
It is not actually Base64: double-check the source really produced Base64.

Is Base64 encryption?

No. Base64 provides no security — it is trivially reversible. Use it to move data safely through text-only channels (URLs, JSON, email), and use real encryption when you need confidentiality.

Ready to decode? Open the Base64 decoder →