Vowel Counter API

About the Vowel Counter API

Perfect for linguistic research, readability analysis, and educational applications requiring detailed phonetic character analysis.

What people use it for

Linguistic Analysis

Analyze vowel patterns and distributions in text for linguistic research

Readability Testing

Assess text complexity based on vowel-consonant ratios

Educational Tools

Create exercises for teaching phonetics and letter recognition

Text Statistics

Generate detailed character frequency reports for writing analysis

Ways to call it

One endpoint, many ways in — REST with JSON, XML, YAML and CSV, plus GraphQL and an MCP interface for AI agents.

JSON

Default REST response

XML

Markup format

YAML

Human-readable

CSV

Tabular export

Beta

GraphQL

Query language

New

MCP

For AI agents

Request parameters — POST /v1/vowelcounter

Sent as JSON in the request body. Premium parameters are accepted on every plan but only take effect on plans that include them. Anything not listed here is dropped rather than passed through.

Required

1
2
3
4

curl -X POST "https://api.apiverve.com/v1/vowelcounter" \
  -H "x-api-key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"text":"The quick brown fox jumps over the lazy dog. This pangram contains every letter of the alphabet at least once."}'

Authentication

Send your key in the x-api-key header. That is the only auth step — no token exchange, and no per-endpoint scope to configure.

Response — POST /v1/vowelcounter

Every APIVerve endpoint returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape.

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19

{
  "status": "ok",
  "error": null,
  "data": {
    "vowels": 31,
    "consonants": 58,
    "totalLetters": 89,
    "vowelPercentage": 34.83,
    "consonantPercentage": 65.17,
    "vowelBreakdown": {
      "a": 8,
      "e": 11,
      "i": 3,
      "o": 7,
      "u": 2
    },
    "textLength": 110
  }
}

Response fields

Paths are relative to data. Premium fields are absent rather than zeroed on plans that do not include them, so check for presence instead of comparing to 0.

Response headers

Every response carries your balance, so your own code always knows where it stands without polling anything. All four are exposed to browsers through CORS.

Errors

Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change.

What a call costs — 2 credits per call

Credits are shared across every APIVerve API — one balance, one key, one bill. Failed requests never count against it, so a rejected input costs nothing.

Calls are what the credits buy at this API's rate — spend them here, on any of the other APIs, or across both. Nothing is reserved per endpoint.

Zero-code embed — one snippet, no backend

Drop an interactive Vowel Counter form onto any page. The widget calls the API for you, so no key ever appears in your markup and there is nothing to deploy.

Changelog — Vowel Counter API

Every change to this endpoint, newest first. Breaking changes ship as a new version and the previous one keeps serving — response fields are added, never removed or retyped in place, so an integration written against v1 keeps working.

Currently v1