Base32 to Decimal Converter

Summary

Base32 is a positional numeral system that uses 32 distinct symbols — the uppercase letters A through Z and the digits 2 through 7 — as defined by RFC 4648. Each Base32 digit represents exactly 5 bits. This tool treats a Base32 string as a pure base-32 integer and converts it to its decimal (base-10) equivalent using BigInt arithmetic, so even very long strings are handled without loss of precision.

How it works

1. Type or paste your Base32 string into the input field.
2. Each character is mapped to its 5-bit value: A=0, B=1, ..., Z=25, 2=26, ..., 7=31.
3. The tool multiplies the running total by 32 and adds each digit value left-to-right.
4. The final decimal integer is displayed along with the equivalent hex and binary representations.
5. Click "Copy" next to any result to copy it to your clipboard.

Use cases

• Decode TOTP secret keys stored as Base32 integers for debugging.
• Convert Base32-encoded identifiers used in URL shorteners to their numeric IDs.
• Verify Base32 encoding implementations by checking the expected integer output.
• Explore positional notation and understand how Base32 relates to binary and decimal.
• Inspect Base32 values produced by Crockford or RFC 4648 encoders.
• Convert Base32 hash fragments to decimal for database lookups.

Frequently Asked Questions