Input
Preparing your workspace…
How to use
- Enter a decimal number, or several numbers on separate lines.
- Read the hexadecimal value and choose uppercase or lowercase.
- Copy the hex digits or inspect the other common bases.
A compact representation for numeric values
Hexadecimal uses sixteen digit values: 0–9 and A–F. Each hex digit corresponds to four binary bits, which makes hex convenient for masks and register values.
The converter starts in decimal-to-hex mode and shows the same number in binary and octal alongside the main output. It does not interpret the number as a color or a memory address.
Representations and workflow
Repeated division by sixteen determines the integer digits. Decimal 65535 becomes FFFF because four hex digits can represent values from 0 through 65535.
65535FFFFEach of the four F digits represents a group of four set binary bits.
Precision and validation
A minus sign remains a minus sign. The tool does not choose an integer width, generate a 0x prefix or reverse bytes for a target CPU.
Interpreting and reusing the result
Copied values preserve integer precision. For fractions, inspect the exact/truncated label before using the displayed expansion in another calculation.
Numbers: up to 500 lines / 1 MiB, at most 4,096 characters per numeral. Fraction output: 1–128 digits. Text and byte data: 64 KiB. Bitwise operations: 8–256 bits. Workers stop after 30 seconds; inputs are not uploaded.
Frequently asked questions
Is the output prefixed with 0x?
No. Copy returns the hex digits and an optional minus sign. Add the prefix if the receiving language or format requires it.
Can I change the letter case?
Yes. Uppercase letters controls A–F in the main result and common-base cards. The numeric value stays the same.
Does this produce little-endian bytes?
No. It converts numeric notation. Hex Byte Reverser is available when you need to change byte order.
Is my input sent to a server?
No. Computation runs in a browser worker. DevToolsy does not upload or store your input.
What does Copy include?
Copy exports the selected displayed value. Download JSON preserves strings and diagnostic codes; it does not turn large numbers into floating-point values.