Decimal to Hex Converter
Convert decimal to hex in your browser, single values or lists, with exact results at any size. Free, instant, nothing uploaded.
About this tool
Convert decimal (base 10) integers to hexadecimal. Paste one number or many, separated by spaces, commas, or newlines, and each converts exactly, at any length, with no 64-bit rounding.
Hex is how those same numbers appear in memory dumps, color codes, MAC addresses, and low-level protocols, so this direction comes up any time you move from human-facing values to machine-facing ones.
Common uses
- Express a numeric ID in the hex form a log or protocol expects.
- Convert RGB channel values (0-255) to their two-digit hex pairs.
- Prepare test values for code that compares against hex constants.
Automate via API
The same conversion is available as a REST endpoint for scripts, pipelines, and backends:
curl -X POST https://payloadly.com/api/v1/tools/decimal-to-hex \ -H "Content-Type: text/plain" \ -H "X-Api-Key: YOUR_API_KEY" \ --data-binary @input.txt
Hex notes
Hexadecimal (base 16) uses the digits 0-9 and a-f, so one hex digit represents exactly four bits. It is the standard notation for memory addresses, byte dumps, color codes, and hashes.
- Hex values are case-insensitive; 0xFF and 0xff are the same number.
- A leading 0x prefix is a convention, not part of the value.
- Each hex digit maps to exactly one 4-bit nibble, which is why hex-binary conversion is mechanical.
Frequently asked questions
Is my data uploaded to a server?
No. This tool runs entirely in your browser using JavaScript, and there are no ads on the page. Nothing you paste or drop here is uploaded, logged, or stored, and you can verify that yourself: open your browser's developer tools and watch the Network tab while you convert (no requests leave the page), or disconnect from the internet after the page loads and keep working.
Is denary the same as decimal?
Yes. Denary is the term used in British schools for base 10, so 'denary to hex' and 'decimal to hex' are the same conversion. Either way, the method is repeated division by 16, keeping the remainders: 500 divided by 16 is 31 remainder 4, then 31 by 16 is 1 remainder 15 (f), then 1: read the remainders back as 1f4.
What about negative numbers?
Enter the absolute value and keep the sign yourself. Negative numbers in real systems are usually two's complement, and the right hex form depends on the width (8, 16, 32, or 64 bits), which a plain number does not carry.
Is there a size limit or a fee?
The browser tool is free with no signup and comfortably handles files up to tens of megabytes (limited by your device's memory). For automated or bulk processing inside your own scripts and pipelines, use the paid REST API.
Related tools
Convert hex to decimal in your browser, one value or a whole list. Arbitrary precision, 0x prefixes handled. Free, instant, no upload.
Convert binary to hex in your browser. Groups bits into nibbles automatically, accepts spaces between groups. Free and instant.
Convert hex, decimal, binary, and octal in one place, in your browser. Auto-detects the input base, handles huge numbers. Free, no upload.
Convert hex to binary in your browser. Digit-by-digit nibble expansion preserves width, handles lists. Free, private, instant.