Curly Quote and Em Dash Highlighter
Paste text and see every smart quote, smart apostrophe, em dash and non-breaking space marked in place, with live counts per category. These are the characters that look fine in a document and then break a grep, a code block, or a diff. Covers the full U+2018-U+201F range, not just the common pair. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (curly-emdash.html, Apache-2.0).
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Details
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System prompt (SKILL.md)
---
name: curly-quote-highlighter
description: Paste text to find the invisible typography - curly quotes, curly apostrophes, em dashes and non-breaking spaces - with live per-category counts.
metadata:
tags:
- artifact-import
- writing
source_url: https://tools.simonwillison.net/curly-emdash
github_repo_url: https://github.com/simonw/tools
---
# Curly Quote and Em Dash Highlighter
An imported Claude artifact. Paste text and it marks every smart quote, smart
apostrophe, em dash and non-breaking space, with a running count for each
category and a highlighted rendering of the passage so you can see where they
sit.
These characters are the ones that look fine in a document and then break
something else: a curly apostrophe that will not match your grep, a
non-breaking space that survives a trim, a smart quote pasted into a code
block, an em dash that gives away where the text came from. This finds them all
at once instead of one failed search at a time.
Detection covers the full smart-quote range (U+2018 through U+201F), not just
the common pair. Counting happens as you type, in the page - nothing is
uploaded, no model is called, and nothing is metered.
Release files (files)
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