Which digits are kept, the leftmost or the rightmost?

The leftmost (most significant) digits are kept, and everything after the Nth digit is discarded. This mirrors how truncating a decimal number's fractional part works, but applied to hex digit positions instead.

Does truncating change a value's numeric meaning?

Yes, usually. Truncation is lossy: removing trailing digits changes the value (unless those digits happened to be trailing zeros), so use this deliberately, not as a formatting-only operation like padding.

What happens to values already shorter than N digits?

They're left completely unchanged; truncation only ever removes digits from values that exceed the limit, it never adds anything to shorter values.

How do I go the other direction and add digits instead?

Use Hex Value Padder, which left-pads shorter values with zeros up to a target width instead of removing digits from longer ones.

Hex Value Truncator - Shorten a Hex List Online

Overview

Introduction

Sometimes a hex value carries more precision or length than you actually need, a full 16-digit identifier when you only care about its first byte, for example, and you need a quick, consistent way to cut it down.

This tool truncates every value in a list of hex values to at most N digits, keeping the leftmost digits and dropping anything past that limit.

What Is Hex Value Truncator?

The Hex Value Truncator is a lossy shortening tool: for any value longer than your chosen digit limit, it keeps only the leading N digits and discards the rest.

Unlike padding, this is not a purely cosmetic change, dropping trailing digits generally changes a value's numeric meaning, so truncation should be used when you specifically want that outcome.

How Hex Value Truncator Works

The input list is parsed and validated as hex values, then each value's digit string is sliced from position 0 up to (but not including) the requested maximum digit count.

A value already at or under that length passes through untouched, since there's nothing to remove.

When To Use Hex Value Truncator

Use this when you deliberately want to shorten hex values to a fixed maximum length, for example extracting just the leading byte of a longer identifier or hash for a quick visual grouping key.

Don't use this if you actually want every value to look the same width without losing information, that's Hex Value Padder's job, since it only ever adds digits rather than removing them.

Often used alongside Hex Value Padder, Hex Number Splitter and Hex Value Sorter.

Features

Advantages

Simple, predictable behavior: always keeps the leftmost N digits, never the rightmost.
Leaves shorter values untouched, so it's safe to run on a list with mixed lengths.
Works the same regardless of how your list is separated (newlines, spaces, or commas).

Limitations

This is a lossy operation for any value longer than the limit; the discarded digits cannot be recovered from the output alone.
Only truncates from the right (dropping trailing digits); there's no option to drop leading digits instead.

Examples

Truncating a mixed-length list to 2 digits

Input

1A2B
FF00
3C, max digits: 2

Output

1A
FF
3C

The first two values are shortened to their leading 2 digits; "3C" is already at the limit and passes through unchanged.

Truncating a single longer value

Input

ABCDEF, max digits: 4

Output

ABCD

Only the first 4 of the 6 input digits are kept; "EF" is discarded.

Best Practices & Notes

Best Practices

Only truncate when you specifically want the shortened value; if you just want visual alignment without losing data, use Hex Value Padder instead.
Double check your chosen digit limit against your longest expected input so you don't accidentally discard meaningful digits.

Developer Notes

Each value is passed through `String.prototype.slice(0, maxDigits)`, which is a no-op for strings already at or under that length, so shorter values are guaranteed to pass through byte-for-byte unchanged.

Hex Value Truncator Use Cases

Extracting just the leading byte (or nibble) of a longer hex identifier for grouping or bucketing
Shortening displayed hex values in a compact UI where full precision isn't needed
Preparing test fixtures that need deliberately truncated (and therefore invalid/changed) values

Common Mistakes

Using truncation when padding was actually intended; truncation discards data, padding doesn't.
Assuming the truncated value is numerically related to the original in any simple way; dropping trailing hex digits is equivalent to integer division by a power of 16, not just a smaller version of the same number.

Tips

If you want to keep the least significant digits instead, reverse your thinking: this tool always keeps the leftmost (most significant) digits.
Chain with Hex Number Analyzer afterward to double-check the truncated value's new decimal equivalent.

Hex Value Truncator