Fill in the Blanks Generator API

GET

Generate fill-in-the-blank trivia puzzles with hints and answers.

Fill in the Blanks Generator creates completion puzzles from idioms, proverbs, quotes, science facts, and geography trivia.

Try it — live request, no key required

Request

GETapi.apiverve.com/v1/fillintheblanks

Verification

Format

No key required to try it. Get a key to use it in your app.

Example

{
  "status": "ok",
  "error": null,
  "data": {
    "puzzles": [
      {
        "id": 1,
        "sentence": "A penny saved is a penny ___.",
        "answer": "EARNED",
        "letterCount": 6,
        "hint": "gained/obtained",
        "firstLetter": null
      },
      {
        "id": 2,
        "sentence": "Actions speak louder than ___.",
        "answer": "WORDS",
        "letterCount": 5,
        "hint": "what we say",
        "firstLetter": null
      },
      {
        "id": 3,
        "sentence": "Don't count your chickens before they ___.",
        "answer": "HATCH",
        "letterCount": 5,
        "hint": "come out of eggs",
        "firstLetter": null
      },
      {
        "id": 4,
        "sentence": "The early bird catches the ___.",
        "answer": "WORM",
        "letterCount": 4,
        "hint": "a crawling creature",
        "firstLetter": null
      },
      {
        "id": 5,
        "sentence": "Don't put all your eggs in one ___.",
        "answer": "BASKET",
        "letterCount": 6,
        "hint": "a container",
        "firstLetter": null
      }
    ],
    "count": 5,
    "difficulty": "medium",
    "category": "idioms",
    "html": "<html><head><title>Fill in the Blanks</title><style>body {font-family: Arial, sans-serif; padding: 20px; max-width: 700px; margin: 0 auto;}h1 {text-align: center; color: #673AB7;}.puzzle {background: #f5f5f5; padding: 20px; margin: 15px 0; border-radius: 10px;}.number {font-weight: bold; color: #673AB7; margin-bottom: 10px;}.sentence {font-size: 18px; line-height: 1.8;}.blank {display: inline-block; min-width: 100px; border-bottom: 2px solid #673AB7; margin: 0 5px;}.hint {font-size: 13px; color: #888; font-style: italic; margin-top: 10px;}.info {font-size: 12px; color: #999; margin-top: 5px;}</style></head><body><h1>Fill in the Blanks</h1><div class='puzzle'><div class='number'>#1</div><div class='sentence'>A penny saved is a penny <span class='blank'></span>.</div><div class='info'>6 letters</div><div class='hint'>Hint: gained/obtained</div></div><div class='puzzle'><div class='number'>#2</div><div class='sentence'>Actions speak louder than <span class='blank'></span>.</div><div class='info'>5 letters</div><div class='hint'>Hint: what we say</div></div><div class='puzzle'><div class='number'>#3</div><div class='sentence'>Don't count your chickens before they <span class='blank'></span>.</div><div class='info'>5 letters</div><div class='hint'>Hint: come out of eggs</div></div><div class='puzzle'><div class='number'>#4</div><div class='sentence'>The early bird catches the <span class='blank'></span>.</div><div class='info'>4 letters</div><div class='hint'>Hint: a crawling creature</div></div><div class='puzzle'><div class='number'>#5</div><div class='sentence'>Don't put all your eggs in one <span class='blank'></span>.</div><div class='info'>6 letters</div><div class='hint'>Hint: a container</div></div></body></html>",
    "image": {
      "imageName": "ba85c6d6-4376-4171-841d-8b4bc97e1095_fillblanks.png",
      "format": ".png",
      "downloadURL": "https://storage.googleapis.com/apiverve/APIData/fillintheblanks/ba85c6d6-4376-4171-841d-8b4bc97e1095_fillblanks.png?GoogleAccessId=635500398038-compute%40developer.gserviceaccount.com&Expires=1766010206&Signature=YRHfh28GKDNvEM4Q07qRcNyg3WnPs7Ee7yg0xXKxKRTmT%2Bg3x%2FThpfWsFTeYScpZlgQTVQ3SU1tZMGH74sZJvAHdVkG6IGA9V2lwIfhHzcfu4Uf4VGKL8%2FIa%2FaLupdtrgDqXSFWOJ9EHHeMKnImAhli1qhlMu%2BIuWAiqfPitDlN5pMklv4R5FACKkZld4LXyA82%2BX8bt%2FESyHciZ5jzlqY1JTacL4kW5uK09bpoo9Ytvs8XOOOjB0my1s%2BIq5z0JEwZzw1Jag%2F5vd09wTXzSXeQMzfo%2FDj73kpU7SilAxEGh%2BuflilyDQTXK7krXcdFUGcD5Nd4Wm%2BW7dP8tQKmbAA%3D%3D",
      "expires": 1766010206793
    }
  }
}

About the Fill in the Blanks Generator API

Returns puzzles with answers, letter counts, and optional hints. Includes printable HTML for offline use.

What people use it for

Education: Create vocabulary and comprehension tests
Language Learning: Build idiom and proverb exercises
Trivia Games: Generate knowledge-testing puzzles
Worksheets: Produce printable educational materials

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
GraphQL: Query language
MCP: For AI agents

View all integrations →

Other ways to use Fill in the Blanks Generator

Same data, same APIVerve account, same credit balance — one key works on all of them.

Give it to an AI agentConnect over MCP and your agent calls it as a native tool — Claude, Cursor, ChatGPT.on VerveKit

Questions.

Common questions about the Fill in the Blanks Generator API.

Read the docs →

What categories of puzzles does the generator support?

Puzzles can be created from idioms, proverbs, quotes, science facts, and geography trivia. You can also specify difficulty levels and choose how many puzzles to generate in each request.

Does each puzzle include clues to help players solve the blank?

Yes. Every puzzle object provides the target answer, the letter count of that answer, and a descriptive hint. Some puzzles also supply the first letter of the missing word.

Can I get printable HTML sheets and puzzle images on the Free plan?

No. Ready-to-print HTML layouts and downloadable puzzle image files are premium features reserved for paid plans. Upgrading to Starter or above unlocks both formatting options.

Will every puzzle always include a first-letter clue?

Not always. The first letter field is populated when available but returns null if one is not provided for that entry. Your interface should handle cases where only the hint and letter count are present.

What would 5,000 puzzle requests cost me?

Each request costs 2 credits, so 5,000 requests use 10,000 credits. That easily fits within the Starter plan, which provides 200,000 credits each month and works out to about $0.30 per 1,000 calls. The Free plan includes 100 calls per month.

Request parameters — GET /v1/fillintheblanks

Sent in the query string. 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.

Optional

Parameter	Type	Example	Description
`category`Optional	string	`idioms`	Puzzle category `randomidiomsproverbsquotessciencegeography` default random
`count`Optional	integer	`5`	Number of puzzles default 5 · range 1-20
`difficulty`Optional	string	`medium`	Difficulty level `easymediumhard` default medium
`image`OptionalPremium	boolean	`true`	Set to true to generate a downloadable puzzle image default false

Example request

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curl "https://api.apiverve.com/v1/fillintheblanks?category=idioms&count=5&difficulty=medium&image=true" \
  -H "x-api-key: YOUR_API_KEY"

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.

Header	When	Value
`x-api-key`Required	Every request	Your API key. Header names are case-insensitive, so `X-API-Key` is the same header.
`Authorization`Alternate	Instead of the above	`Bearer <key>` — for clients that only expose bearer auth. Resolves to the same account and the same billing.

401 is the only auth verdict

A 401 means the key is missing, invalid or expired. A 403 means the key is valid but not permitted here — blocked by a key restriction or an IP allow-list. Running out of credits is a 429.

Response — GET /v1/fillintheblanks

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.

Sample response

{
  "status": "ok",
  "error": null,
  "data": {
    "puzzles": [
      {
        "id": 1,
        "sentence": "A penny saved is a penny ___.",
        "answer": "EARNED",
        "letterCount": 6,
        "hint": "gained/obtained",
        "firstLetter": null
      },
      {
        "id": 2,
        "sentence": "Actions speak louder than ___.",
        "answer": "WORDS",
        "letterCount": 5,
        "hint": "what we say",
        "firstLetter": null
      },
      {
        "id": 3,
        "sentence": "Don't count your chickens before they ___.",
        "answer": "HATCH",
        "letterCount": 5,
        "hint": "come out of eggs",
        "firstLetter": null
      },
      {
        "id": 4,
        "sentence": "The early bird catches the ___.",
        "answer": "WORM",
        "letterCount": 4,
        "hint": "a crawling creature",
        "firstLetter": null
      },
      {
        "id": 5,
        "sentence": "Don't put all your eggs in one ___.",
        "answer": "BASKET",
        "letterCount": 6,
        "hint": "a container",
        "firstLetter": null
      }
    ],
    "count": 5,
    "difficulty": "medium",
    "category": "idioms",
    "html": "<html><head><title>Fill in the Blanks</title><style>body {font-family: Arial, sans-serif; padding: 20px; max-width: 700px; margin: 0 auto;}h1 {text-align: center; color: #673AB7;}.puzzle {background: #f5f5f5; padding: 20px; margin: 15px 0; border-radius: 10px;}.number {font-weight: bold; color: #673AB7; margin-bottom: 10px;}.sentence {font-size: 18px; line-height: 1.8;}.blank {display: inline-block; min-width: 100px; border-bottom: 2px solid #673AB7; margin: 0 5px;}.hint {font-size: 13px; color: #888; font-style: italic; margin-top: 10px;}.info {font-size: 12px; color: #999; margin-top: 5px;}</style></head><body><h1>Fill in the Blanks</h1><div class='puzzle'><div class='number'>#1</div><div class='sentence'>A penny saved is a penny <span class='blank'></span>.</div><div class='info'>6 letters</div><div class='hint'>Hint: gained/obtained</div></div><div class='puzzle'><div class='number'>#2</div><div class='sentence'>Actions speak louder than <span class='blank'></span>.</div><div class='info'>5 letters</div><div class='hint'>Hint: what we say</div></div><div class='puzzle'><div class='number'>#3</div><div class='sentence'>Don't count your chickens before they <span class='blank'></span>.</div><div class='info'>5 letters</div><div class='hint'>Hint: come out of eggs</div></div><div class='puzzle'><div class='number'>#4</div><div class='sentence'>The early bird catches the <span class='blank'></span>.</div><div class='info'>4 letters</div><div class='hint'>Hint: a crawling creature</div></div><div class='puzzle'><div class='number'>#5</div><div class='sentence'>Don't put all your eggs in one <span class='blank'></span>.</div><div class='info'>6 letters</div><div class='hint'>Hint: a container</div></div></body></html>",
    "image": {
      "imageName": "ba85c6d6-4376-4171-841d-8b4bc97e1095_fillblanks.png",
      "format": ".png",
      "downloadURL": "https://storage.googleapis.com/apiverve/APIData/fillintheblanks/ba85c6d6-4376-4171-841d-8b4bc97e1095_fillblanks.png?GoogleAccessId=635500398038-compute%40developer.gserviceaccount.com&Expires=1766010206&Signature=YRHfh28GKDNvEM4Q07qRcNyg3WnPs7Ee7yg0xXKxKRTmT%2Bg3x%2FThpfWsFTeYScpZlgQTVQ3SU1tZMGH74sZJvAHdVkG6IGA9V2lwIfhHzcfu4Uf4VGKL8%2FIa%2FaLupdtrgDqXSFWOJ9EHHeMKnImAhli1qhlMu%2BIuWAiqfPitDlN5pMklv4R5FACKkZld4LXyA82%2BX8bt%2FESyHciZ5jzlqY1JTacL4kW5uK09bpoo9Ytvs8XOOOjB0my1s%2BIq5z0JEwZzw1Jag%2F5vd09wTXzSXeQMzfo%2FDj73kpU7SilAxEGh%2BuflilyDQTXK7krXcdFUGcD5Nd4Wm%2BW7dP8tQKmbAA%3D%3D",
      "expires": 1766010206793
    }
  }
}

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.

Field	Type	Example	Description
`puzzles`	array[5]		Array of fill-in-the-blanks puzzle objects
`id`	number	`1`	Unique identifier for the puzzle
`sentence`	string	`"A penny saved is a penny ___."`	Full sentence with blank to be filled in
`answer`	string	`"EARNED"`	Correct answer word to fill the blank
`letterCount`	number	`6`	Number of letters in the answer
`hint`	string	`"gained/obtained"`	Helpful hint describing the answer
`firstLetter`	object	`null`	First letter of answer or null if not provided
`count`	number	`5`	Total number of puzzles generated
`difficulty`	string	`"medium"`	Difficulty level of the puzzles
`category`	string	`"idioms"`	Category of the puzzles
`html`Premium	string	`"<html><head><title>Fill in the Blanks</title><style>body {font-family: Arial, sans-serif; padding: 20px; max-width: 700px; margin: 0 auto;}…`	Printable HTML rendering of all puzzles
`image`Premium	object	`{...}`	Generated puzzle image details and download information
`imageName`Premium	string	`"ba85c6d6-4376-4171-841d-8b4bc97e1095_fillblanks.png"`	Unique filename of generated puzzle image
`format`Premium	string	`".png"`	Image file format (.png, .jpg, etc)
`downloadURL`Premium	string	`"https://storage.googleapis.com/apiverve/APIData/fillintheblanks/ba85c6d6-4376-4171-841d-8b4bc97e1095_fillblanks.png?GoogleAccessId=63550039…`	Temporary download URL for puzzle image
`expires`Premium	number	`1766010206793`	Timestamp when download URL expires

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.

Header	What it carries
`x-api-remaining-credits`	Credits left in the current cycle
`x-api-credits-used`	Credits spent in the current cycle
`x-api-max-credits`	The allowance for the cycle
`x-api-version`	Version of the endpoint that answered

Errors

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

Status	Meaning	What to do
`400`	Input was rejected	Read `error`; it names the parameter that has to change.
`401`	Key missing or invalid	Check the header name and the key value.
`403`	Key valid, but not permitted here	A key restriction or an IP allow-list — never a bad key.
`429`	Rate limited, or out of credits	Read `error` to tell them apart, then back off or top up.

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.

Plan	Per month	Credits	Fill in the Blanks Generator calls	Per 1,000 calls
Free	Free	200	100	Free
Starter	$29.99	200,000	100,000	$0.30
Pro	$99.99	1,000,000	500,000	$0.20
Mega	$299.99	4,000,000	2,000,000	$0.15

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.

Compare all pricing tiers →

Call it from cURL — GET /v1/fillintheblanks

No SDK to install — this is a plain HTTPS call to /v1/fillintheblanks with your key in the x-api-key header. Swap in a real key and it runs as-is.

cURL

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curl "https://api.apiverve.com/v1/fillintheblanks" \
  -H "x-api-key: YOUR_API_KEY"

Resources

GitHubapiverve/fillintheblanks-apiSource, issues and the examples this page is built from.ReferenceFill in the Blanks Generator API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

@apiverve/fillintheblanksnpm APIVerve.API.FillintheBlanksGeneratorNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Node.js — GET /v1/fillintheblanks

Install the Node.js SDK, then call the Fill in the Blanks Generator API with your key. The client wraps the same HTTPS request, so anything it returns is what the endpoint returns.

Install — npm

npm install @apiverve/fillintheblanks

Node.js

const res = await fetch("https://api.apiverve.com/v1/fillintheblanks", {
  headers: { "x-api-key": "YOUR_API_KEY" },
});
const { data } = await res.json();
console.log(data);

Resources

npm@apiverve/fillintheblanksThe published Node.js client, versioned and signed.GitHubapiverve/fillintheblanks-apiSource, issues and the examples this page is built from.ReferenceFill in the Blanks Generator API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

APIVerve.API.FillintheBlanksGeneratorNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Python — GET /v1/fillintheblanks

No SDK to install — this is a plain HTTPS call to /v1/fillintheblanks with your key in the x-api-key header. Swap in a real key and it runs as-is.

Python

import requests

res = requests.get(
    "https://api.apiverve.com/v1/fillintheblanks",
    headers={"x-api-key": "YOUR_API_KEY"},
)
print(res.json()["data"])

Resources

Also published for

@apiverve/fillintheblanksnpm APIVerve.API.FillintheBlanksGeneratorNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from C# / .NET — GET /v1/fillintheblanks

Install the C# / .NET SDK, then call the Fill in the Blanks Generator API with your key. The client wraps the same HTTPS request, so anything it returns is what the endpoint returns.

Install — NuGet

dotnet add package APIVerve.API.FillintheBlanksGenerator

C# / .NET

using var client = new HttpClient();
client.DefaultRequestHeaders.Add("x-api-key", "YOUR_API_KEY");

var json = await client.GetStringAsync("https://api.apiverve.com/v1/fillintheblanks");
Console.WriteLine(json);

Resources

NuGetAPIVerve.API.FillintheBlanksGeneratorThe published C# / .NET client, versioned and signed.GitHubapiverve/fillintheblanks-apiSource, issues and the examples this page is built from.ReferenceFill in the Blanks Generator API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

@apiverve/fillintheblanksnpm

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Go — GET /v1/fillintheblanks

No SDK to install — this is a plain HTTPS call to /v1/fillintheblanks with your key in the x-api-key header. Swap in a real key and it runs as-is.

req, _ := http.NewRequest("GET", "https://api.apiverve.com/v1/fillintheblanks", nil)
req.Header.Set("x-api-key", "YOUR_API_KEY")

res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))

Resources

Also published for

@apiverve/fillintheblanksnpm APIVerve.API.FillintheBlanksGeneratorNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from PHP — GET /v1/fillintheblanks

No SDK to install — this is a plain HTTPS call to /v1/fillintheblanks with your key in the x-api-key header. Swap in a real key and it runs as-is.

PHP

$ch = curl_init("https://api.apiverve.com/v1/fillintheblanks");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, ["x-api-key: YOUR_API_KEY"]);

$response = curl_exec($ch);
echo $response;

Resources

Also published for

@apiverve/fillintheblanksnpm APIVerve.API.FillintheBlanksGeneratorNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Ruby — GET /v1/fillintheblanks

No SDK to install — this is a plain HTTPS call to /v1/fillintheblanks with your key in the x-api-key header. Swap in a real key and it runs as-is.

Ruby

require "net/http"

uri = URI("https://api.apiverve.com/v1/fillintheblanks")
req = Net::HTTP::Get.new(uri)
req["x-api-key"] = "YOUR_API_KEY"

res = Net::HTTP.start(uri.hostname, uri.port, use_ssl: true) { |h| h.request(req) }
puts res.body

Resources

Also published for

@apiverve/fillintheblanksnpm APIVerve.API.FillintheBlanksGeneratorNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

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Fill in the Blanks Generator API

Try it — live request, no key required

About the Fill in the Blanks Generator API

What people use it for

Ways to call it

Other ways to use Fill in the Blanks Generator

Questions.

Request parameters — GET /v1/fillintheblanks

Optional

Authentication

Response — GET /v1/fillintheblanks

Response fields

Response headers

Errors

What a call costs — 2 credits per call

Call it from cURL — GET /v1/fillintheblanks

Resources

Also published for

Call it from Node.js — GET /v1/fillintheblanks

Resources

Also published for

Call it from Python — GET /v1/fillintheblanks

Resources

Also published for

Call it from C# / .NET — GET /v1/fillintheblanks

Resources

Also published for

Call it from Go — GET /v1/fillintheblanks

Resources

Also published for

Call it from PHP — GET /v1/fillintheblanks

Resources

Also published for

Call it from Ruby — GET /v1/fillintheblanks

Resources

Also published for

Zero-code embed — one snippet, no backend

Changelog — Fill in the Blanks Generator API

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