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Text Simplifier

Turn dense, jargon-heavy writing into plain English, and see the readability score change.

Your text

0 words · 0 / 12,000 chars

Plain version

The plain-English version appears here.

How readability scores work

Readability formulas don’t understand meaning. They measure proxies: how long your sentences are and how long your words are. The most widely used, the Flesch Reading Ease score, was published by Rudolf Flesch in 1948; the Flesch–Kincaid grade level was adapted from it for the US Navy in 1975. Both are still built into word processors today.

Try it: the Flesch Reading Ease score only looks at two things. Drag them and watch the score move.

206.835 − 1.015 × 24 − 84.6 × 1.70 = 38.7

0 hard60 plain English100 easy

Difficult · university · US grade 13.8

Notice the weights: one extra syllable per word costs 84.6 points, while one extra word per sentence costs about 1. That is why swapping long words for short ones moves the score far more than splitting sentences — and why “plain English” advice starts with vocabulary.

Plain-language rules the simplifier follows

  • One idea per sentence, ideally under 20 words.
  • Everyday words: “use” not “utilise”, “start” not “commence”, “about” not “approximately”.
  • Active voice: “The tenant must fix the damage” rather than “Damage shall be remediated”.
  • Explain unavoidable terms the first time they appear.

Questions people ask

How does the text simplifier work?

Choose a target reading level and the AI rewrites your text with shorter sentences, everyday words and active voice, explaining or replacing jargon while keeping every key point. The readability score before and after is calculated in your browser.

What is the Flesch Reading Ease score?

A 0–100 score from Rudolf Flesch's 1948 formula: 206.835 − 1.015 × (words per sentence) − 84.6 × (syllables per word). Higher is easier. 60–70 is plain English; most newspapers sit around 50–60.

What reading level should I aim for?

For the general public, guidance such as the UK Government Digital Service style guide and US plain-language guidelines suggests writing for roughly a 9-to-14-year-old reading age. Grade 6–8 is a sensible target for web pages, instructions and health information.

Will simplifying change the meaning?

It should not, but simplifying legal, medical or financial text can lose precision. Use the plain version to understand or explain; rely on the original for the binding details.

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