Round Hex Numbers
Round hex numbers up or down. Runs entirely in your browser, so your data never leaves your device.
0 chars · 0 lines
Output
The result appears here as you type.
How to use Round Hex Numbers
- 1. Paste the values to round. Enter hex numbers into the input pane, one or many. Rounding operates on each value's numeric magnitude, snapping it to a multiple of 16 raised to your chosen power.
- 2. Choose Trailing nibbles to zero. Trailing nibbles to zero sets the granularity. One nibble rounds to multiples of 0x10, so abcd becomes abc0; two rounds to 0x100 boundaries; three snaps to 0x1000, the usual page-ish alignments.
- 3. Select a Mode. Down truncates toward zero, the safe pick for finding a containing block. Up climbs to the next boundary, matching how allocators pad sizes. Nearest picks whichever boundary is numerically closer.
- 4. Copy the aligned numbers. The rounded values appear in the output pane with the requested trailing zeros. Copy them into your linker script, allocation math or annotated dump.
When to use Round Hex Numbers
Round Hex Numbers snaps hexadecimal values to power-of-16 boundaries, up, down or to the nearest. Alignment questions dominate low-level work, and answering how much a size grows when padded to 0x1000, or which block an address falls in, is exactly what this tool computes without any modular arithmetic by hand.
- Aligning section sizes for a linker. Your firmware section is 0x2f37 bytes and the flash controller writes in 0x100 pages. Rounding up shows the padded size 0x3000 and thus how much slack the layout carries.
- Finding the page containing an address. A crash dump reports a fault at 0x7ffe12c4 and your pages are 0x1000 wide. Rounding down to three trailing zero nibbles gives the page base to look up in the mapping table.
- Bucketing offsets for a histogram. To chart where accesses cluster within a file, round every logged offset down to a 0x100 boundary. The rounded column becomes bucket labels ready for a pivot table.
- Estimating with cleaner numbers. During a design discussion nobody wants to reason about 0x1f4c8. Rounding to the nearest 0x1000 gives a round figure that keeps the whiteboard math tractable.
Examples
Round down 1 nibble
Input
abcd
Output
abc0
Round up 1 nibble
Input
abcd
Output
abd0
About the Round Hex Numbers tool
Round Hex Numbers does its work locally, right in the browser. Round hex numbers up or down. There is no upload step, no queue and no account, and your data never travels over the network.
It belongs to the Hex Tools collection on EditSafely, a set of 108 small, focused Hex utilities that share the same instant, private workspace.
You can shape the output with 2 settings, including Trailing nibbles to zero and Mode, and the result refreshes the moment you change one. 2 worked examples further down the page show exactly what the tool produces for real inputs.
Running locally also makes the tool fast and dependable: results appear as you type or drop a file, there is no server outage that can take it down mid-task, and confidential data can be processed without a second thought.
Frequently asked questions
Does Round Hex Numbers cost anything?
Yes, it is completely free. All 2,658 tools on EditSafely work without an account, a subscription or usage limits.
Is it safe to paste sensitive or confidential data?
No data leaves your device. The whole tool is JavaScript that runs inside your browser tab, so there is no upload, no server-side processing and no log of what you did. If you disconnect from the internet after the page loads, it keeps working.
How much text can I process at once?
There is no fixed limit. Because the work happens on your own device rather than on a shared server, the practical ceiling is your machine's memory, which comfortably handles inputs far larger than typical online tools allow.
Do I need to sign up or install anything?
Nothing to install and no account needed. Open the page in any up-to-date browser, including on a phone or tablet, and the tool is ready.
How do I use the result?
The output panel has a one-click copy button, and you can keep refining the input while you work; the result updates in place as you type.