A free alternative to Hemingway Editor

Readability Check scores writing across six industry-standard formulas — Flesch Reading Ease, Flesch-Kincaid, Gunning Fog, SMOG, Coleman-Liau, and the Automated Readability Index — and highlights every sentence dragging the score down. It runs in your browser, has no paid tier, and requires no download.

What Hemingway gets right

Hemingway Editor, published by the Long brothers in 2014, popularised the idea that sentence-level highlighting is more useful than a single readability number. The web app and its $19.99 desktop sibling have shaped how a generation of writers think about reading level — "go from grade 12 to grade 8" is now a routine editing instruction in marketing teams, content shops, and writing classrooms because of Hemingway.

The product has three real strengths. The sentence-level colour coding is immediately legible. The style flags — adverbs, passive voice, complex phrases — catch common bad-prose patterns. And the single grade-level readout at the top of the page is honest, not jargon-laden.

Where Hemingway falls short

Three meaningful gaps for users who need more than a creative-writing coach:

• One formula, not six. Hemingway uses its own variant of the Automated Readability Index (ARI). For most general-audience writing the result is reasonable. But the Hemingway grade can disagree by 2–3 grades with the consensus across the six standard formulas, particularly on technical or jargon-heavy text — and Hemingway does not show you that disagreement.
• No audience targeting. A "good" grade depends on who you are writing for. AMA patient material targets grade 6. Legal disclosures target grade 11. Hemingway shows the same single grade regardless of the audience you are writing for; you have to remember the target in your head.
• The free version is web-only; the desktop app costs $19.99. The web version is fine for one-off scoring but does not save documents, has no embed, and shows no formula breakdown. Anything beyond that is paid.

What this calculator does differently

• Six formulas, one consensus. The home page shows all six scores live — Flesch Reading Ease (0–100), Flesch-Kincaid Grade, Gunning Fog, SMOG, Coleman-Liau, and ARI — plus an averaged consensus grade. Outliers across the six tell you what's actually wrong: Gunning Fog spike means jargon; SMOG spike means complex-word density; Flesch-Kincaid alone moving means sentence length.
• Audience presets. Pick "general public", "middle school", "legal / compliance", "technical / professional", "academic", or "children K–6" and every score card shows a ✓ / ⚠ indicator against the target range. Edit until everything is green.
• Sentence-length distribution chart. A live chart shows the words-per-sentence curve across your draft. Long-tail spikes flag the rewrites that will move the score the most.
• Free forever, no account. Free desktop-equivalent functionality with no $19.99 paywall. Funded by display advertising on reference pages, not on the calculator itself.
• Embeddable. Drop a single iframe tag into your own site to share the tool with readers — useful for writing-craft blogs, style-guide internal docs, and content-marketing teams.

Side-by-side

When Hemingway is still the right choice

Three cases:

• You want passive-voice and adverb flagging. Readability Check does not replicate these style flags — they are not part of any standard readability formula. If your editing pass is focused on prose style rather than reading level, Hemingway's flags are useful in a way our tool is not.
• You prefer one number to six. Hemingway's single grade is honest and unambiguous. The six-formula consensus we show is more defensible but takes a beat longer to read.
• You already own the $19.99 desktop app and the offline-document workflow fits your team. Switching tools mid-stream rarely pays off.

For everything else — multi-formula scoring, audience-target editing, embedding the tool, free use at any volume — the case for Readability Check is straightforward.

How the sentence highlighting works

The annotated text panel applies the same colour vocabulary Hemingway popularised, but with calibrated thresholds:

• Green — sentences of 15 words or fewer. Comfortable to read.
• Amber — 16–25 words. Medium; should be split if the sentence is dense.
• Red — over 25 words. Rewrite candidate.
• Wavy amber underline — words of four or more syllables. These drive Gunning Fog and SMOG scores aggressively.

Hover any highlighted sentence for a tooltip with the word count. The summary line above the annotated panel reports the count of red sentences and complex words.

Audience match: the missing feature in Hemingway

Pick a preset from the dropdown above the verdict panel. Each preset defines a target Flesch-Kincaid grade ceiling and a Flesch Reading Ease floor:

• General public: FK ≤ 9, FRE ≥ 60
• Middle school: FK ≤ 8, FRE ≥ 65
• Legal / compliance: FK ≤ 11, FRE ≥ 45
• Technical / professional: FK ≤ 14, FRE ≥ 30
• Academic: FK ≤ 16, FRE ≥ 20
• Children K–6: FK ≤ 6, FRE ≥ 80

Each formula row gets a ✓ "in target" or ⚠ "above target" indicator that updates as you edit. The same readability number means different things for different readers, and the audience preset surfaces that explicitly — which Hemingway's one-grade-fits-all readout doesn't.

Frequently asked questions