Microsoft Word's readability score — how to find it, what it means

Microsoft Word has shipped a readability scorer in the box since Office 97. Most users never find it because it lives behind a checkbox in the proofing options and only fires at the end of a spell-check. Here is how to switch it on, how to interpret the two numbers it produces, and what Word is not telling you.

Where Word hides readability statistics

The readability check is off by default in every version of Word. To enable it:

1. Windows: File → Options → Proofing
2. Mac: Word → Preferences → Spelling & Grammar
3. Scroll to the section labelled When correcting spelling and grammar in Word.
4. Tick the box Show readability statistics.
5. Click OK.

From now on, every time you finish a spell-check (Review tab → Spelling & Grammar, or press F7), Word opens a small readability dialog at the end with a single column of numbers. Close the spelling pane without finishing the check and the readability box never appears.

What the readability box actually shows

Word reports five categories of numbers in its readability dialog:

The two readability scores are the headline numbers. Flesch Reading Ease runs 0–100; higher is easier. Flesch-Kincaid Grade Level returns a US school grade. Word does not compute Gunning Fog, SMOG, Coleman-Liau, or ARI — so it cannot give you a consensus across multiple formulas. It also does not flag which sentences are dragging the score down.

How to interpret Word's two scores

For most general-audience writing, target a Flesch Reading Ease of 60–70 and a Flesch-Kincaid Grade of 7–9. For plain-language compliance work (US Plain Writing Act, GDPR Article 12), target Flesch-Kincaid 8 or below.

The most common surprise: Word's readability box also reports passive sentences as a percentage. It is not a formula score — it is a style flag. Aim for under 20% for plain writing; aggressive plain-language work targets under 10%.

What Word leaves out

Word's readability dialog is useful but limited. Four meaningful gaps:

• Only two formulas. Six formulas are in common use today. SMOG (used in healthcare), Gunning Fog (preferred for business and policy writing), Coleman-Liau and ARI (character-based, more reliable on technical text). Word reports neither. A score that lands at FK 9 on Word might score SMOG 11 — that gap matters if the audience is patients or non-specialists.
• No sentence-level highlighting. Word tells you the average sentence length but not which specific sentences are too long. You have to scan the document by eye.
• No complex-word flagging. Words with three or more syllables drive the Fog and SMOG scores. Word doesn't surface them.
• Triggered only by spell-check. To re-score after edits, you have to run a full spell-check again. There is no "score now" button.

Why Word's readability check only happens after spell-check

This is the most common point of confusion. Microsoft tied readability statistics to the Spelling & Grammar tool deliberately — readability was framed as a final-polish step, not a live editing aid. The design choice has held since Office 97 and Microsoft has not changed it.

The practical effect: re-scoring after a paragraph rewrite means clicking through every dialog box of a fresh spell-check. For drafts where readability is the priority (patient information, plain-language policy work), the friction adds up. A live-scoring browser tool is faster for iterative editing.

A faster workflow when Word's two scores aren't enough

Use Word's readability box for the final-polish reading on a finished document. Use a multi-formula browser tool while you are still rewriting.

1. Draft in Word as usual.
2. When a section needs work, copy it into our browser calculator — six formulas update as you type, sentences are highlighted by length, and complex words are underlined.
3. Edit until the consensus grade matches your audience target (a built-in selector covers general public, K–6 children, legal/compliance, technical, and academic presets).
4. Paste the revised text back into Word.
5. Run Word's spell-check + readability dialog as the final compliance reading.

Workflow for plain-language compliance

If you are writing US Plain Writing Act material, GDPR Article 12 notices, AMA-target patient information, or CMS Summary of Benefits forms, the two-formula readout in Word is not enough.

For healthcare specifically, AMA recommends a SMOG score of 6 or below for patient material — and SMOG is the formula Word does not compute. For governance and business writing, the Gunning Fog Index penalises jargon more aggressively than Flesch-Kincaid and tends to be the truer signal. A practical workflow scores against all six and trusts the consensus, then uses Word for the final check.

Does Word Online have readability?

No. The free browser version of Word (part of Microsoft 365 web) does not include the readability statistics dialog. The feature only exists in the installed desktop client (Word 2016 and later on Windows, Word for Mac 2016 and later). If you only have access to Word Online, score in a separate tool.

What about Google Docs?

Google Docs does not have a built-in readability scorer at all. Third-party add-ons exist but require document-level permissions. The simplest workflow is to paste a section into a browser calculator while keeping your draft in Docs.

Frequently asked questions