A writing editor that shows you where AI leaked into your prose.
Paste your draftIt's important to note that writing matters.
Let's delve into review your draft.
This tool provides a comprehensive framework for helps you write better.
I created Markup for myself. AI was creeping into my writing, subtly at first, then more and more, until I could smell it.
I stopped using LLMs as ghostwriter, and asked ChatGPT to be my writing coach instead.
Two problems with this:
1. AI chatbot feedback is hard to actually use.
The moment the writing was longer than one page, a suggestion to remove XYZ was hard to find and apply in my writing.
2. The feedback is general and "obvious."
I compared what I got from Claude or ChatGPT to insights from podcast interviews with famous writers. The AI felt very vanilla compared to the human experts.
Markup solves both.
Markup is a visual editor, powered by an LLM. Suggestions and feedback happen right in the editor, not in a chat window.
I built different lenses, each one like handing your draft to a different editor. One catches AI smell, another checks clarity the way author Steven Pinker would. There are 5 more lenses, and more on the way.
Stay human out there.
— Nate
Drop your content into the editor — blog post, newsletter, tweet thread, whatever.
We flag the robotic patterns and explain what makes each one land wrong.
For each flag, you get rewrite options — from minimal fixes to full rewrites. Your call.
It sounds like you wrote it. Because you did.
"Doesn't smell like AI" is a low bar.
Once the robotic stink is gone, markup.fyi has other lenses. Switch to Pinker's clarity principles and find zombie nouns and hedging. Each lens explains why something reads wrong, so you learn the pattern.
Most people come for the AI detector. They keep the tab open for the other lenses.
Detect patterns that reveal AI-generated text
Elevate prose clarity using Steven Pinker's principles
Catch analogy, authority, and dogma before they harden
Write with punch, clarity, and edge
Move from safe abstraction to vulnerable truth
Stress-test ideas with first-hand, plainspoken thinking
Start free with AI detection. Upgrade for all lenses, higher limits, and document workflows.
Billed annually at $144