Free Baby Age Calculator API
Turn a birth date into an exact age, a zodiac sign, a birthstone, and milestone dates. Free, no key, no sign-up. CORS is open, so you can call it from anywhere. GET /api returns this list as JSON.
Endpoints
/api/age/Turn a birth date into an exact age, zodiac sign, birthstone, milestones, and special days.
/api/zodiac/All 12 zodiac signs with date ranges, element, nickname, and a guide_url each. One GET request, no key, no sign-up.
/api/milestones/All 25 baby milestone guides with day count, age group, and a guide_url each. One GET request, no key, no sign-up.
/api/birthstones/The birthstones for all 12 months, each with its stones and a guide_url. One GET request, no key, no sign-up.
/api/birthstones/{month}/Everything the month's birthstone page shows: each stone's colors, hardness, sources and story, plus keepsake ideas, a safety note, zodiac signs, and quick answers.
Every response has the same shape
{
"code": "200 - mirrors the HTTP status",
"data": "the payload, null on error",
"error": "null on success, { message } on error",
"meta": "API name, docs links, attribution - same on every response"
}Errors use the same envelope: HTTP 400 with data: null and an error.message that says what to fix.
One friendly rule
When you show this data to people, please link the guide_url pages so they can read the full guides. That's what keeps the API free.
Building an AI agent? Machine-readable docs live at /llms.txt.