Both Flesch Reading Ease Calculator and Font Size Readability sit in the Writing & Text category. They share an underlying model (string walk with style rules) but target different outcomes: Flesch Reading Ease on one side, Font Size Readability on the other.
Photo: Aaron Burden on Unsplash
Score 60-70 = standard. 90 5th grade.
16px body min web. Smaller is unreadable
| Attribute | Flesch Reading Ease Calculator | Font Size Readability |
|---|---|---|
| Category | Writing & Text | Writing & Text |
| Primary input | Source text, target style, optional rules | Source text, target style, optional rules |
| Primary output | Flesch Reading Ease result, derived from the inputs above | Font Size Readability result, derived from the inputs above |
| Math model | String walk with style rules | String walk with style rules |
| Best for | Flesch Reading Ease estimate and decision support | Font Size Readability estimate and decision support |
| Runs in browser | Yes, no data leaves your device | Yes, no data leaves your device |
| Login required | No | No |
| Cost | Free | Free |
Under the hood, Flesch Reading Ease Calculator uses string walk with style rules fed by source text, target style, optional rules. Font Size Readability uses string walk with style rules fed by source text, target style, optional rules. The two are not substitutes; they answer adjacent questions in your workflow.
Pick Flesch Reading Ease Calculator when your question is about flesch reading ease and your inputs are source text, target style, optional rules. Pick Font Size Readability when the question shifts to font size readability and your inputs become source text, target style, optional rules. If neither matches what you need, the Writing & Text category hub lists every tool we have for related questions.
Your task is editing, formatting, and writing checks and you already have source text, target style, optional rules. The output you need is a transformed text or count.
Your task is editing, formatting, and writing checks and you have source text, target style, optional rules. The output you need is a transformed text or count.
Browse the Writing & Text hub for related tools, or the Writing & Text hub for the other side.
Flesch Reading Ease Calculator is designed to answer questions about flesch reading ease using source text, target style, optional rules. Font Size Readability is designed for font size readability using source text, target style, optional rules. They are complementary tools that target different inputs and outputs.
Use Flesch Reading Ease Calculator when your task is flesch reading ease estimate and decision support and you need a flesch reading ease result, derived from the inputs above from source text, target style, optional rules.
Use Font Size Readability when the question is font size readability estimate and decision support and your inputs are source text, target style, optional rules. The result is a font size readability result, derived from the inputs above.
Yes. Both run entirely in your browser, require no login, and are free to use without limits. Your inputs are not transmitted to any server.
Accuracy depends on the inputs you provide, not on the tool. Flesch Reading Ease Calculator uses string walk with style rules and is accurate for flesch reading ease when its inputs are correct. Font Size Readability uses string walk with style rules and is accurate for font size readability under the same condition.