---
title: "Readability Checker"
method: POST
path: "/api/v1/tools/readability-checker"
tags: ["tools"]
---

# Readability Checker

`POST /api/v1/tools/readability-checker`

## Request

- Base URL: `https://toolforte.com`
- URL: `https://toolforte.com/api/v1/tools/readability-checker`
- Auth: HTTP bearer

Score how hard a text is to read with six named formulas: Flesch Reading Ease, Flesch-Kincaid Grade, Gunning Fog, SMOG, Coleman-Liau and the Automated Readability Index. Each is returned under its own name alongside the word, sentence and syllable counts it was built from, plus the mean grade, the school year it maps to and the audience that suits.

## Request body

- object
  - `text` string

## Response `200`

Successful result

- object
  - `ok` boolean
  - `data` object
    - `words` integer
    - `sentences` integer
    - `syllables` integer
    - `complexWords` integer
    - `letters` integer
    - `averageWordsPerSentence` integer
    - `averageSyllablesPerWord` number
    - `scores` object
      - `fleschReadingEase` number
      - `fleschKincaidGrade` number
      - `gunningFog` integer
      - `smogIndex` number
      - `colemanLiauIndex` number
      - `automatedReadabilityIndex` number
    - `averageGrade` number
    - `gradeLabel` string
    - `audience` string
    - `fleschLabel` string

## Other responses

- `400`: Missing or invalid request fields
- `401`: Invalid or missing API key
- `429`: Monthly plan limit reached

---

[API](https://skmtc.dev/toolforte/apis/toolforte-api.md) · [All operations](https://skmtc.dev/toolforte/apis/toolforte-api/llms.txt) · [OpenAPI document](https://skmtc.dev/toolforte/apis/toolforte-api/revisions/4d814d484dfc?raw)