Age Calculator API

GET

Convert any date of birth into exact age, next birthday, and age in words.

Age Calculator converts a date of birth into exact age broken down by years, months, weeks, days, hours, minutes, and seconds. It also provides the age in written words and a countdown to the next birthday.

Try it — live request, no key required

Request

GETapi.apiverve.com/v1/agecalculator?dob=1990-01-01

Query parameters

dobstring

Verification

Format

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

Example

{
  "status": "ok",
  "error": null,
  "data": {
    "dob": "1990-01-01",
    "age_breakdown": {
      "years": 35,
      "months": 431,
      "weeks": 1876,
      "days": 13133,
      "hours": 315208,
      "minutes": 18912499,
      "seconds": 1134749976
    },
    "age_words": {
      "years": "thirty-five",
      "ordinal": "thirty-fifth",
      "full": "thirty-five years old",
      "locale": "en-US"
    },
    "timezone": "America/Chicago",
    "locale": "en-US",
    "next_birthday": {
      "months": 0,
      "weeks": 2,
      "days": 15,
      "hours": 367,
      "minutes": 22060,
      "seconds": 1323623
    },
    "insights": {
      "generation": "Millennial",
      "zodiacSign": "Capricorn",
      "chineseZodiac": "Horse",
      "birthstone": "Garnet",
      "dayOfWeekBorn": "Monday",
      "isLeapYearBirth": false,
      "milestones": {
        "canVoteUS": true,
        "canDrinkUS": true,
        "canRentCarUS": true,
        "seniorDiscount": false
      }
    }
  }
}

About the Age Calculator API

Age Calculator works by analyzing the date of birth provided and calculating the age. It uses advanced algorithms to calculate the age based on the date of birth and returns the calculated age.

What people use it for

User Onboarding Verification: When a new user registers, verify their exact age in years from their birth date before activating account features.
Birthday Campaign Scheduling: Marketing platforms track the countdown to each customer's next birthday in days and hours to trigger timely promotional discount codes.
Pediatric Patient Intake: Health record systems record patient age broken down into months and weeks for infants who need age-specific developmental checks.
Profile Milestone Cards: Display a user's age written out in words on community profile cards and count down to their next birthday celebration.

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 Age Calculator

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 Google Sheets or ExcelA =VERVE() formula fills a column — no script, no export, recalculates in place.on VerveSheets Ground an agent on itA cited, machine-checkable fact your model can't produce on its own.on VerveContext

Questions.

Common questions about the Age Calculator API.

Read the docs →

Is it cheap enough to calculate age for every user registration?

Yes. Each lookup costs 2 credits, which works out to $0.0003 per calculation on the Starter plan, or about $0.30 per 1,000 users. Starter includes 100,000 lookups each month, while the Free plan gives you 100 calculations monthly for testing.

What units of age breakdown does the response return?

The API calculates age in complete years, total months, weeks, days, hours, minutes, and seconds. It also generates the age spelled out in natural language words and calculates a full countdown to the person's next birthday.

Are legal milestones and generational cohorts included on the Free plan?

No. Generational cohort, zodiac signs, birthstone, day of the week born, leap year status, and legal milestone checks like US voting or drinking age are premium fields. Any paid plan, starting with Starter, unlocks all of them.

What date format does the API require?

The date of birth parameter must be formatted strictly as YYYY-MM-DD. You can also optionally provide an IANA timezone string, such as America/Chicago, so the API can accurately determine what day counts as today when calculating age.

Which legal milestones can the API verify?

On paid plans, the insights object checks several US-specific thresholds. These include whether the person is of legal age to vote, legally allowed to drink alcohol, eligible to rent a car, or qualified for senior citizen discounts.

Request parameters — GET /v1/agecalculator

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.

Required

Parameter	Type	Example	Description
`dob`Required	string	`1990-08-02`	The date of birth to calculate the age from (format: YYYY-MM-DD) date

Optional

Parameter	Type	Example	Description
`timezone`Optional	string	`America/Chicago`	IANA timezone used to interpret the date of birth and to determine "today" when computing the age default America/Chicago · timezone

Example request

1
2

curl "https://api.apiverve.com/v1/agecalculator?dob=1990-01-01&timezone=America%2FChicago" \
  -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/agecalculator

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": {
    "dob": "1990-01-01",
    "age_breakdown": {
      "years": 35,
      "months": 431,
      "weeks": 1876,
      "days": 13133,
      "hours": 315208,
      "minutes": 18912499,
      "seconds": 1134749976
    },
    "age_words": {
      "years": "thirty-five",
      "ordinal": "thirty-fifth",
      "full": "thirty-five years old",
      "locale": "en-US"
    },
    "timezone": "America/Chicago",
    "locale": "en-US",
    "next_birthday": {
      "months": 0,
      "weeks": 2,
      "days": 15,
      "hours": 367,
      "minutes": 22060,
      "seconds": 1323623
    },
    "insights": {
      "generation": "Millennial",
      "zodiacSign": "Capricorn",
      "chineseZodiac": "Horse",
      "birthstone": "Garnet",
      "dayOfWeekBorn": "Monday",
      "isLeapYearBirth": false,
      "milestones": {
        "canVoteUS": true,
        "canDrinkUS": true,
        "canRentCarUS": true,
        "seniorDiscount": false
      }
    }
  }
}

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
`dob`	string	`"1990-01-01"`	Date of birth as provided in request (format: YYYY-MM-DD)
`age_breakdown`	object	`{...}`	Age expressed in years, months, weeks, days, hours, minutes, and seconds
`years`	number	`35`	Person's age in complete years
`months`	number	`431`	Total age in months
`weeks`	number	`1876`	Total age in weeks
`days`	number	`13133`	Total age in days
`hours`	number	`315208`	Total age in hours
`minutes`	number	`18912499`	Total age in minutes
`seconds`	number	`1134749976`	Total age in seconds
`age_words`	object	`{...}`	Age expressed in words (e.g., thirty-five years old)
`years`	string	`"thirty-five"`	Age in written word form (e.g., thirty-five)
`ordinal`	string	`"thirty-fifth"`	Age in ordinal word form (e.g., thirty-fifth)
`full`	string	`"thirty-five years old"`	Age as complete phrase (e.g., thirty-five years old)
`locale`	string	`"en-US"`	Locale used for word generation (e.g., en-US)
`timezone`	string	`"America/Chicago"`	Timezone associated with the calculation (e.g., America/Chicago)
`locale`	string	`"en-US"`	Locale code for the response (e.g., en-US)
`next_birthday`	object	`{...}`	Countdown to next birthday in months, weeks, days, hours, minutes, seconds
`months`	number	`0`	Months until next birthday
`weeks`	number	`2`	Weeks until next birthday
`days`	number	`15`	Days until next birthday
`hours`	number	`367`	Hours until next birthday
`minutes`	number	`22060`	Minutes until next birthday
`seconds`	number	`1323623`	Seconds until next birthday
`insights`	object	`{...}`	Derived facts about the date of birth: generation, zodiac signs, birthstone, weekday born and US legal milestones
`generation`Premium	string	`"Millennial"`	Generational cohort (e.g., Millennial, Gen Z, Baby Boomer)
`zodiacSign`Premium	string	`"Capricorn"`	Western zodiac sign based on birth date (e.g., Capricorn, Leo)
`chineseZodiac`Premium	string	`"Horse"`	Chinese zodiac animal based on birth year (e.g., Dragon, Tiger)
`birthstone`Premium	string	`"Garnet"`	Traditional birthstone for birth month (e.g., Diamond, Ruby)
`dayOfWeekBorn`Premium	string	`"Monday"`	Day of the week person was born (e.g., Monday, Friday)
`isLeapYearBirth`Premium	boolean	`false`	Whether the person was born in a leap year
`milestones`Premium	object	`{...}`	Legal milestones achieved (canVoteUS, canDrinkUS, canRentCarUS, seniorDiscount)
`canVoteUS`Premium	boolean	`true`	Whether person is eligible to vote in United States elections
`canDrinkUS`Premium	boolean	`true`	Whether person is legal age to drink alcohol in United States
`canRentCarUS`Premium	boolean	`true`	Whether person meets age requirement to rent cars in United States
`seniorDiscount`Premium	boolean	`false`	Whether person is eligible for senior citizen discounts

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	Age Calculator 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/agecalculator

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

cURL

1
2

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

Resources

GitHubapiverve/agecalculator-apiSource, issues and the examples this page is built from.ReferenceAge Calculator API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

@apiverve/agecalculatornpm apiverve-agecalculatorPyPI APIVerve.API.AgeCalculatorNuGet

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/agecalculator

Install the Node.js SDK, then call the Age Calculator 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/agecalculator

Node.js

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

Resources

npm@apiverve/agecalculatorThe published Node.js client, versioned and signed.GitHubapiverve/agecalculator-apiSource, issues and the examples this page is built from.ReferenceAge Calculator API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

apiverve-agecalculatorPyPI APIVerve.API.AgeCalculatorNuGet

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

Call it from Python — GET /v1/agecalculator

Install the Python SDK, then call the Age Calculator API with your key. The client wraps the same HTTPS request, so anything it returns is what the endpoint returns.

Install — PyPI

pip install apiverve-agecalculator

Python

import requests

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

Resources

PyPIapiverve-agecalculatorThe published Python client, versioned and signed.GitHubapiverve/agecalculator-apiSource, issues and the examples this page is built from.ReferenceAge Calculator API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

@apiverve/agecalculatornpm APIVerve.API.AgeCalculatorNuGet

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/agecalculator

Install the C# / .NET SDK, then call the Age Calculator 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.AgeCalculator

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/agecalculator");
Console.WriteLine(json);

Resources

NuGetAPIVerve.API.AgeCalculatorThe published C# / .NET client, versioned and signed.GitHubapiverve/agecalculator-apiSource, issues and the examples this page is built from.ReferenceAge Calculator API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

@apiverve/agecalculatornpm apiverve-agecalculatorPyPI

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

Call it from Go — GET /v1/agecalculator

No SDK to install — this is a plain HTTPS call to /v1/agecalculator 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/agecalculator", 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/agecalculatornpm apiverve-agecalculatorPyPI APIVerve.API.AgeCalculatorNuGet

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

Call it from PHP — GET /v1/agecalculator

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

PHP

$ch = curl_init("https://api.apiverve.com/v1/agecalculator");
curl_setopt($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/agecalculatornpm apiverve-agecalculatorPyPI APIVerve.API.AgeCalculatorNuGet

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

Call it from Ruby — GET /v1/agecalculator

No SDK to install — this is a plain HTTPS call to /v1/agecalculator 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/agecalculator")
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/agecalculatornpm apiverve-agecalculatorPyPI APIVerve.API.AgeCalculatorNuGet

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

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Age Calculator API

Try it — live request, no key required

About the Age Calculator API

What people use it for

Ways to call it

Other ways to use Age Calculator

Questions.

Request parameters — GET /v1/agecalculator

Required

Optional

Authentication

Response — GET /v1/agecalculator

Response fields

Response headers

Errors

What a call costs — 2 credits per call

Call it from cURL — GET /v1/agecalculator

Resources

Also published for

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

Resources

Also published for

Call it from Python — GET /v1/agecalculator

Resources

Also published for

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

Resources

Also published for

Call it from Go — GET /v1/agecalculator

Resources

Also published for

Call it from PHP — GET /v1/agecalculator

Resources

Also published for

Call it from Ruby — GET /v1/agecalculator

Resources

Also published for

Zero-code embed — one snippet, no backend

Changelog — Age Calculator API

Calendar

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