What this tool does
Number Base Converter converts numbers between decimal, binary, hexadecimal, octal, and bases up to 36.
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🔢 Number Base Converter
Convert binary, octal, decimal, and hexadecimal values with auto-detection, exact BigInt output, copyable reports, and typed validation errors.
Base conversion checks
Validates digits against the selected source base, accepts common 0b/0o/0x prefixes, removes spaces/underscores as separators, and warns when values exceed JavaScript’s safe integer range.
Why it is useful
It helps developers, students, and hardware tinkerers inspect IDs, flags, bytes, colors, and low-level values.
How it works
The browser parses the input with the selected or auto-detected base, then renders equivalent values as exact integer strings.
Best input
Use digits valid for the selected base. Prefixes like 0b, 0o, and 0x are supported for binary, octal, and hex.
Debugging tip
For signed integers, byte order, or fixed-width values, confirm representation rules outside the base conversion itself.
Privacy note
Base conversion runs locally in your browser.
Important limitation
Base conversion does not by itself define signedness, overflow, endian order, or fixed-width integer behavior.
Quick answers
What is hexadecimal used for?
Hex is common for bytes, colors, memory addresses, flags, encoded IDs, and low-level debugging.
Why did conversion fail?
The input may contain digits not valid for the selected base.
Common Use Cases
Decode binary or hex flags
Convert 0b and 0x values into decimal while preserving exact text output.
Check embedded or low-level values
Translate between octal permissions, decimal IDs, and hexadecimal memory-style values.
Share conversion evidence
Copy a report or JSON summary for documentation, debugging, or agent workflows.