Hex Values to File Converter

Parses a whitespace- or newline-separated list of hex values, each of any digit width (e.g. 1a, 2f, 00ff, abcdef), interprets each as its own integer, and packs each into the minimum number of big-endian bytes needed, concatenated into a downloadable binary file. A free online tool from Staaarter, right in your browser.

Runs locallyUpdated 2026-07-26

Overview

Introduction

Sometimes the hex data you have isn't a clean, fixed-width byte stream, it's a list of individually meaningful values, like register values, opcodes, or IDs, each written with however many digits felt natural.

This tool takes exactly that kind of list and turns it into a real binary file, sizing each value's bytes to what it actually needs rather than forcing every token to the same width.

What Is Hex Values to File Converter?

A converter that reads a whitespace- or newline-separated list of hex tokens, parses each one as an independent integer, and encodes each as the minimum number of big-endian bytes that integer requires.

It's the flexible counterpart to this category's Hex Bytes to File Converter, which instead requires one continuous hex string split strictly into two-digit byte pairs.

How Hex Values to File Converter Works

The input is split on whitespace (spaces, tabs, newlines) into tokens; each token is validated as hex digits (an optional 0x prefix is tolerated and stripped).

Leading zeros are stripped from each token (keeping at least one digit) so the byte count reflects the value's actual magnitude, then the remaining digits are padded to an even count if needed and split into byte pairs, most-significant byte first.

Every token's bytes are concatenated in order into one Uint8Array, which is offered as a downloadable file.

When To Use Hex Values to File Converter

Use this tool when you have a list of separate hex values of varying width, register dumps, ID lists, or similar, that you want packed into a compact binary file.

If instead you have one single continuous hex string meant to be read strictly two digits at a time (the standard hex-to-binary conversion), use the Hex Bytes to File Converter tool instead.

Features

Advantages

  • Each value is sized independently, so you don't need to manually pad every token to a common width.
  • Accepts a natural, human-typed list format (whitespace or newline separated, optional 0x prefixes).
  • Runs entirely client-side; the file is generated and downloaded locally.

Limitations

  • Because leading zeros are stripped by value, you can't use this tool to force a specific fixed byte width per token; use the Hex Bytes to File Converter for exact, strict byte-pair control.
  • Very large token lists may be slow to process in the browser; there's no hard cap, but extremely long input isn't recommended.
  • Whitespace is the only supported separator; commas or other delimiters between tokens aren't recognized.

Examples

Mixed-width token list

Input

1a 2f 00ff abcdef

Output

1A 2F FF AB CD EF (6 bytes total)

"1a" and "2f" each need 1 byte, "00ff" strips to value 0xFF which also needs only 1 byte, and "abcdef" needs 3 bytes, giving 6 bytes total in the downloaded file.

A single small value

Input

5

Output

05 (1 byte total)

A single hex digit is padded to a full byte (0x05) since the minimum byte count for any value, including small ones, is one byte.

Best Practices & Notes

Best Practices

  • Double check the byte preview panel before downloading, since leading-zero stripping can produce a smaller file than you might expect from the digit counts you typed.
  • Use the Hex Bytes to File Converter tool instead if you need every byte pair preserved literally, with no value-based resizing.
  • Separate tokens clearly with spaces or newlines; other punctuation between values isn't treated as a separator.

Developer Notes

Each token is processed by stripping leading zeros with a regex that keeps at least one digit (so zero itself still yields a single 0x00 byte), left-padding to an even digit count if needed, then splitting into two-digit chunks parsed with `parseInt(chunk, 16)`; all tokens' bytes are concatenated via `Uint8Array.set` in order.

Hex Values to File Converter Use Cases

  • Packing a list of register or opcode values into a small binary test fixture
  • Building a binary file from a list of IDs or codes written in hex
  • Converting a mixed-width hex value list from documentation into an actual file
  • Quickly generating a short binary blob for testing a parser

Common Mistakes

  • Expecting "00ff" to always produce two bytes; because this tool sizes by value, it collapses to one byte (0xFF) unless you need the full two bytes, in which case use Hex Bytes to File Converter instead.
  • Using commas or other punctuation as separators; only whitespace (spaces, tabs, newlines) splits tokens.
  • Mixing this tool up with the strict Hex Bytes to File Converter when a fixed, literal byte-pair mapping is actually what's needed.

Tips

  • Check the byte-count preview after conversion, it's the fastest way to confirm the output matches what you expected.
  • Prefix a token with 0x if that's how your source data is written; it's stripped automatically before parsing.

References

Frequently Asked Questions