What Does "SGVsbG8gV29ybGQ=" Decode To?
SGVsbG8gV29ybGQ= decodes to "Hello World". This is standard Base64 decoding. The Base64 alphabet maps each character back to a 6-bit value, the bits are recombined into 8-bit bytes, and the padding = indicates the original data was 11 bytes (not a multiple of 3).
How to Decode Base64
JavaScript
atob('SGVsbG8gV29ybGQ=');
// "Hello World"Python
import base64
base64.b64decode('SGVsbG8gV29ybGQ=').decode()
# 'Hello World'Bash
echo 'SGVsbG8gV29ybGQ=' | base64 --decode
# Hello WorldNode.js
Buffer.from('SGVsbG8gV29ybGQ=', 'base64').toString();
// "Hello World"Try It Yourself
Use our Base64 Encode & Decode tool to decode any Base64 string instantly in your browser.
Frequently Asked Questions
How do I decode a Base64 string?
In JavaScript use atob('...'), in Python use base64.b64decode('...').decode(), or in Bash use echo '...' | base64 --decode.
What if the Base64 string contains invalid characters?
Valid Base64 uses only A-Z, a-z, 0-9, +, /, and = for padding. If you see - or _ instead of + and /, the string is using Base64url encoding. Convert - to + and _ to / before decoding.