What is Base64 encoding?

Base64 is a binary-to-text encoding scheme that represents binary data using 64 printable ASCII characters (A-Z, a-z, 0-9, +, /). It is widely used to embed binary data in JSON, HTML, email, and URLs.

What does the decimal output represent?

Each decimal number (0-255) is the integer value of a single decoded byte. For example, the ASCII character "A" has a decimal value of 65, hex 0x41, and binary 01000001.

What is the combined integer value shown for small inputs?

For inputs up to 8 bytes, the tool interprets the full byte sequence as a single big-endian unsigned integer, which is how multi-byte numbers are commonly stored in network protocols and binary file formats.

Does this tool handle padding characters?

Yes. Trailing = padding characters are automatically handled before decoding, as they are structural markers and do not represent data bytes.

What is the difference between Base64 and decimal?

Base64 is a text representation of binary data. Decimal (base-10) is the numeric value of each byte in the decoded data. This tool bridges both by decoding Base64 text to its original bytes and then showing each byte as a decimal integer.

Can I decode Base64 images or large files?

You can paste any valid Base64 string. For large payloads the byte table is capped at 512 rows for readability, but the total byte count and full decimal list are still computed.

Base64 to Decimal Converter

Name: Base64 to Decimal Converter
Availability: InStock
Author: Nham Vu

Paste a Base64 string and instantly see the decimal value of each decoded byte alongside its hex, binary, and printable character.

Base64 Input

Decimal Output

Enter a Base64 string and click Decode

#	Dec	Hex	Binary	Char

Copied!

Summary

Paste a Base64 string and instantly see the decimal value of each decoded byte alongside its hex, binary, and printable character.

How it works

Paste or type a Base64 string into the input field.
The tool decodes the string using the standard Base64 alphabet (A-Z, a-z, 0-9, +, /).
Each decoded byte is converted to its decimal (0-255) integer value.
Results display the decimal value, hex value, binary representation, and printable character for every byte.
For inputs up to 8 bytes, a combined unsigned integer value is also computed.
Use the Copy button to export the decimal values as a space-separated list.

Use cases

Inspect the raw byte values of Base64-encoded tokens or payloads.
Understand how text characters map to decimal numbers at the byte level.
Debug Base64-encoded data by examining individual decimal byte values.
Convert Base64 color codes or small integers back to their numeric form.
Verify encoded data integrity by checking byte values against a specification.
Learn how decimal, hex, and binary relate through hands-on byte inspection.
Analyze multi-byte integer encoding in network protocols or file formats.
Decode Base64-wrapped numeric data in JWT tokens or binary payloads.

Frequently Asked Questions

Last updated: 2026-06-13 · Reviewed by Nham Vu