Readability Calculator API

POST https://api.findutils.com/api/tools/readability-calculator/execute

Compute six readability scores for English text (Flesch Reading Ease, Flesch-Kincaid Grade, Gunning Fog, SMOG, Coleman-Liau, Automated Readability Index) plus an average grade level, a reading-level label, a target audience, and text statistics. Scores are null when the text has fewer than 10 words.

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Request body

application/json

text

string required

The text to analyse (at least 10 words for scores).

Example arguments

Verified

{
  "text": "The cat sat on the mat. The dog sat on the rug. Both were happy."
}

curl -X POST https://api.findutils.com/api/tools/readability-calculator/execute \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "text": "The cat sat on the mat. The dog sat on the rug. Both were happy."
  }'

const response = await fetch('https://api.findutils.com/api/tools/readability-calculator/execute', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json', Authorization: 'Bearer YOUR_API_KEY' },
  body: JSON.stringify({"text":"The cat sat on the mat. The dog sat on the rug. Both were happy."}),
});
const data = await response.json();

import requests

response = requests.post(
    "https://api.findutils.com/api/tools/readability-calculator/execute",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={"text":"The cat sat on the mat. The dog sat on the rug. Both were happy."},
)
data = response.json()

$ch = curl_init('https://api.findutils.com/api/tools/readability-calculator/execute');
curl_setopt_array($ch, [
    CURLOPT_POST => true,
    CURLOPT_HTTPHEADER => ['Content-Type: application/json', 'Authorization: Bearer YOUR_API_KEY'],
    CURLOPT_POSTFIELDS => '{"text":"The cat sat on the mat. The dog sat on the rug. Both were happy."}',
    CURLOPT_RETURNTRANSFER => true,
]);
$data = json_decode(curl_exec($ch), true);

Also an MCP tool

Call readability_calculator from Claude, Cursor or any MCP client. Same arguments, same output.

https://mcp.findutils.com

MCP reference

Rate limit: 60 a minute, per IP
Auth: API key
REST id: readability-calculator
MCP name: readability_calculator
Category: Text
Machine-readable: openapi.json · markdown.md

Request body

Example arguments

More Text tools

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