Skip to main content

See the whole site Free

Reading level

A Flesch–Kincaid grade for each post on English-language sites, in the editor sidebar, against a target of grade 9.

Overview

Lumtera measures reading level with the Flesch–Kincaid grade formula and shows it near the top of the block editor's Accessibility sidebar, for example "Grade 8.2 · Easy to read". The same line appears in the Lumtera panel inside Elementor. It is recalculated with every check, a moment after you stop typing.

Each grade gets a plain label: Very easy to read up to grade 6, Easy to read up to 9, Fairly difficult up to 12, and Difficult to read above that. When a post is above grade 9, the sidebar adds a tip: shorter sentences and simpler words help everyone, and WCAG 3.1.5 (AAA) suggests offering a plain summary.

Only visible prose is counted: paragraphs, list items, headings, table cells, quotes and captions. Headings and list items without a full stop count as sentences of their own, so a list of short points does not push the grade up. The measurement needs at least 100 words; below that, no grade is shown.

Why it matters

Long sentences and long words shut out people with cognitive and learning disabilities, people reading in a second language, and anyone in a hurry. WCAG 3.1.5 (AAA) suggests content readable at about lower secondary level.

What you get

  • Flesch–Kincaid grade level shown in the editor sidebar.
  • Target grade 9, based on WCAG 3.1.5.
  • Calculated when the site language is English and a post has 100 words or more, where the formula is meaningful.

How it works

  1. Write your post

    Once it passes 100 words, the reading level appears in the sidebar.

  2. Simplify where it helps

    Shorter sentences and everyday words bring the grade down.

Who it helps

  • Public-sector and health sites

    Writing for a wide audience is part of the job. A visible grade gives writers a quick signal before content goes to review.

  • Marketing and support teams

    The grade shows when a draft has drifted into long, dense sentences that readers skim past.

  • Audiences reading in a second language

    Shorter sentences help people reading English as a second language, and the tip reminds writers to add a summary when a topic needs complex words.

Good to know

How it behaves, what it needs, and where its limits are.

Follows the site language
The grade is calculated when the site language is a form of English. It does not detect each post's language, so a post in another language on an English site still gets a grade made for English.
Information, not an issue
Reading level never creates an issue, never changes the score and never affects publishing.
A formula, not a judgment
Flesch–Kincaid counts words, sentences and estimated syllables. It cannot tell whether text is clear, well organized or right for its readers.
Why grade 9
Grade 9 matches the lower secondary education level that WCAG 3.1.5 refers to. That criterion is level AAA, so the target is guidance rather than an AA requirement.
For developers
The lumtera_readability_supported filter turns the measurement on or off. Turning it on for another language shows a grade, but the formula and syllable counting are still built for English.

Questions

Something else on your mind? Contact support

Does it work for other languages?

Not yet. The grade is shown when the site language is English, because the formula is designed for English. Developers can switch the measurement on or off with the lumtera_readability_supported filter.

Why does my short post show no grade?

Below 100 words the formula gives unreliable results, so Lumtera leaves it out.

Does reading level affect my score?

No. The score counts errors and items needing review only.

Can I see it in the classic editor?

No. The grade appears in the block editor sidebar and the Elementor panel.

What lowers the grade fastest?

Split long sentences and prefer short, everyday words. Breaking a dense paragraph into a list or adding subheadings also helps, because each list item and heading counts as a sentence of its own. Watch the grade change as you edit.

More in “See the whole site”

Start with the free plugin today

All 64 checks, the editor sidebar, Elementor panel and site report — free, with no account and no page limits.