Percentage Recalculator
Enter percentages, tick the ones to exclude, and see the rest renormalised to sum to 100 - with the active total shown as you go. For the everyday case of reporting a split among respondents who actually picked a side, without leaving a chart whose bars add to 91%. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (percentage-recalculator.html, Apache-2.0).
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---
name: percentage-recalculator
description: Drop options out of a set of percentages and see the rest renormalised to 100%.
metadata:
tags:
- artifact-import
- data
source_url: https://tools.simonwillison.net/percentage-recalculator
github_repo_url: https://github.com/simonw/tools
---
# Percentage Recalculator
An imported Claude artifact. Enter up to four percentages, tick "Ignore this"
on any you want excluded, and the remaining values are rescaled so they sum to
100 again - with the running total of what is still active shown alongside.
The everyday version of this problem: a poll reports 38/31/22/9 including
"don't know", and you want the split among people who actually picked a side.
Dividing each survivor by the surviving total is easy to get subtly wrong by
hand, and easy to forget entirely - which is how a chart ends up with bars that
add to 91%.
Recalculation runs as you type, on numbers only. Nothing is uploaded, no model
is called, and nothing is metered.
Release files (files)
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