Name: Spell Check API: Bing Spell Check Replacement
Brand: tidydata
SKU: api-tidydata-spell-check
Availability: InStock
Author: API Market

TidyData

# Spell Check API

## Overview

The Spell Check API finds spelling errors in English text and suggests fixes. Each error comes with its offset, length and token, a type (UnknownToken, Variant, Capitalization or RepeatedToken) and up to 10 suggestions ranked with a 0 to 1 score. The response also includes corrected, the full text with the best suggestion applied, ready for a "Did you mean...?" prompt. It handles US and UK variants (color and colour), proper nouns written in lowercase, repeated words such as "the the" and fused words such as "alot", and it skips URLs, emails, mentions, hashtags, code in backticks, camelCase names and acronyms.

GET /v1/spellcheck suits short inputs and POST /v1/spellcheck accepts long text as plain text, JSON or a form field, up to 20,000 characters. The dictionary has 167,000 words from SCOWL plus modern terms, and you can add your own brand names or jargon with words. For teams moving off the Bing Spell Check API, which Microsoft retired in August 2025, format=bing returns the same response shape and the mkt and mode parameters are accepted. It fits forms, chat and comment apps, CMS and email editors, search suggestions and data cleaning.

## Features

*   **2 endpoints**: GET for short text and POST for long text sent as plain text, JSON {"text": "..."} or a form field.
*   **US, UK or any English**: language accepts en-US (default), en-GB or en, and flags spellings from the other variant.
*   **Ranked suggestions**: 1 to 10 suggestions per error (default 4), each with a 0 to 1 score, plus an auto-corrected text.
*   **Four error types**: UnknownToken, Variant, Capitalization and RepeatedToken, with offset and length for highlighting.
*   **Custom words and skipping**: Accept your own terms with words; URLs, emails, mentions, hashtags, code and ALL-CAPS acronyms are skipped.
*   **Bing Spell Check format**: format=bing returns the Bing Spell Check v7 response shape for drop-in migration.
*   **10 requests per second**: Every plan, including pay as you go, allows up to 10 requests per second, and each call needs only the x-api-market-key header.

## Use Cases

*   **Forms, comments and chat**: Underline misspelled words as users type and offer the top suggestion.
*   **CMS and email editors**: Check articles and newsletters before publishing, with brand names added through words.
*   **Search "did you mean"**: Use the corrected text to suggest a fixed query when a search returns no results.
*   **Data cleaning**: Find misspelled product titles and names in catalogs and CRM exports.
*   **Bing Spell Check migration**: Replace calls to the retired Bing API by switching the URL and adding format=bing.

## API Documentation

### Base URL

All requests go through the API.market gateway at this base URL:

```
https://prod.api.market/api/v1/tidydata/spell-check
```

### Authentication

Every request needs your API.market key in the `x-api-market-key` header:

```
x-api-market-key: YOUR_API_KEY
```

Replace `YOUR_API_KEY` with your actual API key.

### Endpoints

#### 1. Check spelling

Checks the text query parameter and returns each error with offset, type and ranked suggestions, plus the corrected text. Add format=bing for the Bing Spell Check v7 shape.

**Method:** `GET`

**Endpoint:** `/v1/spellcheck`

**Parameters:**

| Name | In | Description | Type | Required | Default | Max Value |
|---|---|---|---|---|---|---|
| `text` | query | Text to check (max 20,000 characters) | string | Yes | - | - |
| `language` | query | en-US (default), en-GB or en (any English). Also accepts mkt=en-US like Bing | string | No | - | - |
| `mode` | query | proof (default: spelling + repeated words) or spell (spelling only) | string | No | - | - |
| `max_suggestions` | query | 1-10 suggestions per error (default 4) | string | No | - | - |
| `words` | query | Comma-separated custom words to accept (brand names, jargon) | string | No | - | - |
| `ignore_uppercase` | query | Skip ALL-CAPS words like acronyms (true/false, default true) | string | No | - | - |
| `format` | query | Leave empty for the full response, or bing for the Bing Spell Check v7 response shape | string | No | - | - |

**Example Request:**

```bash
curl -X GET "https://prod.api.market/api/v1/tidydata/spell-check/v1/spellcheck?text=I%20recieve%20alot%20of%20emails%20abuot%20the%20the%20project.&language=en-US&mode=proof&max_suggestions=4&words=TidyData%2CKubernetes&ignore_uppercase=true&format=" \
  -H "x-api-market-key: YOUR_API_KEY"
```

**Example Response (200 OK, abridged):**

```json
{
  "language": "en-US",
  "mode": "proof",
  "words_checked": 9,
  "errors_count": 4,
  "corrected": "I receive a lot of emails about the project.",
  "errors": [
    {
      "offset": 2,
      "length": 7,
      "token": "recieve",
      "type": "UnknownToken",
      "suggestions": [
        {
          "suggestion": "receive",
          "score": 0.698
        },
        {
          "suggestion": "relieve",
          "score": 0.418
        },
        {
          "suggestion": "revive",
          "score": 0.241
        }
      ]
    },
    {
      "offset": 10,
      "length": 4,
      "token": "alot",
      "type": "UnknownToken",
      "suggestions": [
        {
          "suggestion": "a lot",
          "score": 0.923
        },
        {
          "suggestion": "allot",
          "score": 0.604
        },
        {
          "suggestion": "alto",
          "score": 0.604
        }
      ]
    },
    {
      "offset": 25,
      "length": 5,
      "token": "abuot",
      "type": "UnknownToken",
      "suggestions": [
        {
          "suggestion": "about",
          "score": 0.698
        },
        {
          "suggestion": "abbot",
          "score": 0.389
        },
        {
          "suggestion": "abut",
          "score": 0.337
        }
      ]
    }
  ],
  "note": "Dictionary spell checker (no AI, deterministic). Types: UnknownToken (misspelling), Variant (spelling of the other English variant, e.g. colour in en-US), Capitalization (proper noun written in lowercase), RepeatedToken (\"the the\", proof mode). Add format=bing for the response shape of the retired Bing Spell Check API v7. Word lists: SCOWL, Copyright 2000-2018 Kevin Atkinson."
}
```

#### 2. Check spelling of long text

Same check for text sent in the body as plain text, JSON {"text": "..."} or a text= form field, up to 20,000 characters. Takes the same query options as GET.

**Method:** `POST`

**Endpoint:** `/v1/spellcheck`

**Parameters:**

| Name | In | Description | Type | Required | Default | Max Value |
|---|---|---|---|---|---|---|
| `language` | query | en-US (default), en-GB or en (any English). Also accepts mkt=en-US like Bing | string | No | - | - |
| `mode` | query | proof (default: spelling + repeated words) or spell (spelling only) | string | No | - | - |
| `max_suggestions` | query | 1-10 suggestions per error (default 4) | string | No | - | - |
| `words` | query | Comma-separated custom words to accept (brand names, jargon) | string | No | - | - |
| `ignore_uppercase` | query | Skip ALL-CAPS words like acronyms (true/false, default true) | string | No | - | - |
| `format` | query | Leave empty for the full response, or bing for the Bing Spell Check v7 response shape | string | No | - | - |
| (body) | body | Request body as `text/plain`. | text/plain | Yes | - | - |

**Example Request:**

```bash
curl -X POST "https://prod.api.market/api/v1/tidydata/spell-check/v1/spellcheck?language=en-US&mode=proof&max_suggestions=4&words=TidyData%2CKubernetes&ignore_uppercase=true&format=" \
  -H "x-api-market-key: YOUR_API_KEY" \
  -H "Content-Type: text/plain" \
  -d 'Their going to definately acommodate us untill tommorow.'
```

**Example Response (200 OK, abridged):**

```json
{
  "language": "en-US",
  "mode": "proof",
  "words_checked": 8,
  "errors_count": 4,
  "corrected": "Their going to definitely accommodate us until tomorrow.",
  "errors": [
    {
      "offset": 15,
      "length": 10,
      "token": "definately",
      "type": "UnknownToken",
      "suggestions": [
        {
          "suggestion": "definitely",
          "score": 0.595
        },
        {
          "suggestion": "defiantly",
          "score": 0.271
        },
        {
          "suggestion": "definably",
          "score": 0.122
        }
      ]
    },
    {
      "offset": 26,
      "length": 10,
      "token": "acommodate",
      "type": "UnknownToken",
      "suggestions": [
        {
          "suggestion": "accommodate",
          "score": 0.649
        }
      ]
    },
    {
      "offset": 40,
      "length": 6,
      "token": "untill",
      "type": "UnknownToken",
      "suggestions": [
        {
          "suggestion": "until",
          "score": 0.698
        },
        {
          "suggestion": "untie",
          "score": 0.271
        },
        {
          "suggestion": "till",
          "score": 0.153
        }
      ]
    }
  ],
  "note": "Dictionary spell checker (no AI, deterministic). Types: UnknownToken (misspelling), Variant (spelling of the other English variant, e.g. colour in en-US), Capitalization (proper noun written in lowercase), RepeatedToken (\"the the\", proof mode). Add format=bing for the response shape of the retired Bing Spell Check API v7. Word lists: SCOWL, Copyright 2000-2018 Kevin Atkinson."
}
```

## Status Codes

| Code | Status | Description |
|---|---|---|
| 200 | OK | The request succeeded and the result is in the response body. |
| 400 | Bad Request | A required parameter is missing or a value is invalid. The body explains the problem. |
| 401 | Unauthorized | The `x-api-market-key` header is missing, invalid or expired. |
| 403 | Forbidden | Your subscription does not include this endpoint. |
| 404 | Not Found | The requested item or path does not exist. |
| 429 | Too Many Requests | You went over 10 requests per second or used up your plan quota. |
| 500 | Internal Server Error | Something failed while processing the request. Retry after a short delay. |

## Rate Limits

Every plan allows 10 requests per second. The Pro plan includes 25,000 calls a month and the Ultra plan 150,000; when a monthly quota is used up, further calls return `429 Too Many Requests` until the next billing period. The pay-as-you-go plan has no quota and bills US$0.0005 per successful call. If you receive a `429`, back off before retrying and honour any `Retry-After` header.

## FAQ

**How do I migrate from Bing Spell Check?**

Send the same text and add format=bing. The response uses the Bing Spell Check v7 shape, with _type "SpellCheck" and flaggedTokens holding offset, token, type and suggestions with scores. The mkt=en-US and mode=proof or spell parameters are accepted too.

**What is the difference between proof and spell mode?**

proof (the default) checks spelling and also flags repeated words such as "the the". spell checks spelling only.

**Does it catch grammar mistakes?**

No. It is a dictionary spell checker. Correctly spelled words used in the wrong place, such as "Their going" instead of "They're going", are not flagged.

**How do I stop it flagging brand names?**

Pass them in words as a comma-separated list, for example words=TidyData,Kubernetes. ALL-CAPS acronyms are skipped by default; set ignore_uppercase=false to check them.

**How long can the text be?**

Up to 20,000 characters. Use POST with a plain-text, JSON or form body for anything longer than a sentence or two.

**How much does it cost, and is there a free plan?**

There is no free plan. Pay as you go costs US$0.0005 per call with no monthly fee. Pro is US$4.99 per month for 25,000 calls and Ultra is US$14.99 per month for 150,000 calls. All plans allow 10 requests per second.

## Contact Us

If you have any questions or need assistance, you can reach out to us through the embedded chat on the bottom right corner of the page or send an email to hello@magicapi.com.


Find English spelling errors with offsets, ranked suggestions and a corrected text. US and UK spelling, custom words and a Bing Spell Check v7 response format.