Best Readability Checkers in 2026
Updated
In short: Readability Formulas is ranked #1 of 25 as of 4 October 2026, ahead of ProWritingAid and TextGears. The best-ranked option with a free plan is ProWritingAid. The lowest first paid tier on this page is Hemingway Editor at $0.69/mo.
When you want to assess how easy a piece of writing is to follow, readability checkers offer different forms of analysis and feedback. Compare readability formulas and sentence analysis, then look at whether clarity recommendations support the kind of revision you have in mind. Language support matters if you review writing in multiple languages, while a browser extension may affect how you access checks as you work. Readability Formulas, ProWritingAid, and TextGears are among the entries to compare. API access may be useful for programmatic workflows; also weigh free-plan availability and paid-from pricing against the features you need.
25 readability checkers ranked on what their makers publish — plans and prices, free tiers, platforms and the facts on their own pages.
8 of the 25 here have a free tier you can use, 0 have open-source code on record, and 0 have full bars: free, open, on most of your devices and documented.
| # | App | Signal | Free tier | Open code | Devices | From | Score |
|---|---|---|---|---|---|---|---|
| 1 | Readability FormulasWeb · Windows · Mac · Extension | Three bars | — | 3 of 6 | Free | 6.5 | |
| 2 | ProWritingAidExtension | Two bars | — | 0 of 6 | $10/mo | 6.4 | |
| 3 | TextGearsWeb · API | Two bars | — | 1 of 6 | $2.48/mo | 6.4 | |
| 4 | AnchorKite Readability CheckerWeb | Two bars | — | 1 of 6 | Free | 6.3 | |
| 5 | Check ReadabilityWeb · Extension | Two bars | — | 1 of 6 | Free | 6.3 | |
| 6 | Delimiter Readability CheckerWeb | Two bars | — | 1 of 6 | Free | 6.3 | |
| 7 | Text InspectorWeb · API | Two bars | — | 1 of 6 | Free | 6.3 | |
| 8 | Slick WriteWeb | One bar | — | 1 of 6 | Free | 6.2 | |
| 9 | Hemingway EditorWeb · Windows · Mac | Two bars | — | — | 3 of 6 | $0.69/mo | 5.6 |
| 10 | Eclipse Readability StudioWindows · Mac · Linux | One bar | — | — | 3 of 6 | — | 5.2 |
| 11 | Readability Analysis Tool (RAT)Windows · Linux | No signal | — | — | 2 of 6 | — | 5.2 |
| 12 | Analyze My WritingWeb | No signal | — | — | 1 of 6 | — | 5.1 |
| 13 | ApyHub Readability Scores Documents APINo platforms listed | No signal | — | — | 0 of 6 | — | 5.1 |
| 14 | ATOS AnalyzerWeb | No signal | — | — | 1 of 6 | — | 5.1 |
| 15 | Botoi Readability APINo platforms listed | No signal | — | — | 0 of 6 | — | 5.1 |
| 16 | Data·yze Readability AnalyzerWeb | No signal | — | — | 1 of 6 | — | 5.1 |
| 17 | DO101 Readability CheckerWeb | No signal | — | — | 1 of 6 | — | 5.1 |
| 18 | Flesch-Kincaid CalculatorWeb | No signal | — | — | 1 of 6 | — | 5.1 |
| 19 | Flesch-Kincaid Readability & Grade Level AnalyzerWeb | No signal | — | — | 1 of 6 | — | 5.1 |
| 20 | Readability.chWeb | No signal | — | — | 1 of 6 | — | 5.1 |
| 21 | ReadabilityToolWeb | No signal | — | — | 1 of 6 | — | 5.1 |
| 22 | UsingEnglish Text AnalyserWeb | No signal | — | — | 1 of 6 | — | 5.1 |
| 23 | ReadableWeb · API | One bar | — | — | 1 of 6 | $12/mo | 4.9 |
| 24 | StyleWriterWindows | One bar | — | — | 1 of 6 | $90/mo | 4.8 |
| 25 | OrwellixWeb | No signal | — | — | 1 of 6 | — | 4.7 |
Is your app on this list?
Numbered spots on this list can be sponsored. They are labelled, and the editorial order and scores never change for payment.
Questions about this list
Which readability checker is ranked first on Freedom251?
Readability Formulas is ranked #1 of 25 with a score of 6.5. ProWritingAid is second and TextGears third.
How many of these have a free plan?
8 of the 25 on this page publish a free plan on their own pricing pages.
Which is the cheapest paid option?
On this page, Hemingway Editor has the lowest first paid tier we found: $0.69/mo.
How is this list ranked?
Ranked free-and-open first: a usable free tier and open-source code, then the platforms it runs on and its documentation. Paid placements never change a rank.