Decode from Base64 format

▶ Overview

base64convert.org is a free online Base64 converter that lets you encode text or files to Base64 format and decode Base64 back to readable text or binary files — instantly, with no sign-up required. Whether you're debugging API tokens, embedding images as data URIs, or working with JWT payloads, this tool has you covered.

Base64 encoding schemes are commonly used when binary data needs to be stored or transferred over text-based channels — such as email (MIME), JSON APIs, XML documents, or HTML data URIs. Our tool supports standard Base64, URL-safe Base64, files up to 100MB, multiple character sets, and live in-browser mode.

How to Use the Base64 Converter

1. Choose the Decode or Encode tab at the top of the page.
2. Paste your text into the input box, or upload a file using the file picker.
3. Select the correct character set (UTF-8 works for most modern content).
4. Click the DECODE or ENCODE button.
5. Copy the result with the Copy to clipboard button.

Advanced Options

• Character set: Specifies the text encoding used when the Base64 was originally created. UTF-8 is the default and correct for almost all modern content.
• Decode each line separately: Useful when you have multiple Base64 values, one per line. Each line is decoded independently.
• Live mode: Decodes or encodes in real-time as you type, using your browser's built-in JavaScript — zero data is sent to our servers.

Common Use Cases

• Data URIs: Embed images, fonts, or scripts directly in HTML/CSS without external file requests.
• JWT debugging: Decode the payload section of a JSON Web Token to inspect claims.
• API authentication: HTTP Basic Auth encodes credentials as Base64 (username:password).
• Email attachments: MIME encodes binary attachments in Base64 for safe text-channel transfer.
• Config files: Kubernetes secrets and CI/CD tools store binary values as Base64 in YAML/JSON.
• Cryptographic keys: PEM-encoded certificates and SSH keys are Base64 inside ASCII headers.

Base64 Code Examples

JavaScript (browser & Node.js):

// Encode
const encoded = btoa("Hello, World!");
// → "SGVsbG8sIFdvcmxkIQ=="

// Decode
const decoded = atob("SGVsbG8sIFdvcmxkIQ==");
// → "Hello, World!"

// Node.js (Buffer)
const enc = Buffer.from("Hello").toString("base64");
const dec = Buffer.from(enc, "base64").toString("utf8");

Python:

import base64

encoded = base64.b64encode(b"Hello, World!").decode("utf-8")
decoded = base64.b64decode("SGVsbG8sIFdvcmxkIQ==").decode("utf-8")
url_safe = base64.urlsafe_b64encode(b"Hello+World")

PHP:

$encoded = base64_encode("Hello, World!");
$decoded = base64_decode("SGVsbG8sIFdvcmxkIQ==");

Safe and Secure

All connections to base64convert.org use HTTPS encryption. Uploaded files are deleted immediately after processing. Downloadable results are removed after the first download or 15 minutes of inactivity. We never store or inspect the contents of your submitted data. Use Live Mode to keep everything entirely in your browser.

How Base64 Encoding Works

Base64 takes every 3 bytes of binary input (24 bits) and splits them into four 6-bit groups. Each 6-bit group maps to one of 64 printable characters. This is why Base64 output is always ~33% larger than the original: 3 bytes become 4 characters. If the input length isn't divisible by 3, padding characters (=) are added.

Frequently Asked Questions