Pass the date to parse it. Add to= to count days between two dates. Bare /date?to= counts from today.

ISO, spelled months in both orders (March 29, 2026 and 29 Aug 2026), numeric like 3/29/2026, and compact 20260829. A leading weekday and an ISO time tail are ignored.

What about 03/04/2026?

March 4th or April 3rd, both are real days, so it answers valid: false. Pass format=mdy or format=dmy to assert a reading. 3/29/2026 resolves on its own, since 29 cannot be a month. We never guess.

How do I count days between dates?

Add to=. /date/2026-08-29?to=2026-12-25 appends to and days: 118. Signed, so a past date goes negative. Bare /date?to= counts from today.

What week numbering is this?

Add deep=true for calendar detail on every plan. deep.week and deep.week_year use ISO 8601: weeks start Monday, and the week-year can differ from the calendar year near January 1.

Anything that does not resolve to one real calendar day, including two-digit years. Junk answers valid: false as a 200, never a 404.

GET /date/{date} · ?to=

Date API

Pass a date any way it was written. Get one clean answer, or the days between two.

You have a date, any format. Get one ISO day.

Example response/date/March%2029,%202026

{
  "date": "2026-03-29",
  "valid": true,
  "unix": 1774742400,
  ?deep=true
}

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What comes back.

date

The date as ISO YYYY-MM-DD, or the input echoed when it does not parse

valid

Resolves to one real calendar day. Ambiguous numeric dates answer false without ?format=

deep.weekday_name

English weekday name

deep.week

ISO 8601 week number

deep.day_of_year

Day of year, 1 to 366

deep.quarter

Quarter, 1 to 4

deep.leap

Whether the year is a leap year

unix

Unix time at midnight UTC of that date, seconds

With ?to= only: the other date, normalized ISO

days

With ?to= only: signed days from the date to ?to=. Future positive, past negative

Pass the mess

March 29, 2026, 3/29/2026, 29 Aug 2026, or 20260829. A weekday and a time tail are ignored.

Get the facts

ISO date, validity, and Unix time. Add deep=true for calendar detail on every plan. Ambiguous 03/04 answers valid false, never a guess.

Count the days

Add to= for the signed days between two dates. Bare /date?to= counts from today.

ISO 8601
week numbering: 0
guessed readings

Pass a date as a spreadsheet, form, or log wrote it. ISO, March 29, 2026, 29 Aug 2026, 3/29/2026, and 20260829 resolve to an ISO date, validity, and Unix timestamp. A leading weekday and ISO time tail are ignored.

Add deep=true for calendar components, ISO week and week-year, day of year, quarter, leap year, and days in the month. Detail is included on every plan.

Ambiguous 03/04/2026 returns valid: false until you pass format=mdy or format=dmy. Add to for signed days between dates; bare /date?to= counts from today.

SPEED

How long /date takes.

Median time to first byte over the last seven days. Warm requests, measured every 30 minutes. Live verification and other request variants can take longer.

20ms

APAC

36ms

LatAm

26ms

88ms

See live status →

Make your first request.

One key works across the APIs. Copy a request in your language and get JSON back.

curl "https://api.parseapi.com/date/March%2029,%202026" \
  -H "X-API-Key: YOUR_API_KEY" \
  -H "Parse-Version: 2.0.0"

// Example response · 200
{
  "date": "2026-03-29",
  "valid": true,
  "unix": 1774742400
}

API reference SDKs Keys and authentication

Every response field

Response fields

date: The date as ISO YYYY-MM-DD, or the input echoed when it does not parse
valid: Resolves to one real calendar day. Ambiguous numeric dates answer false without ?format=
unix: Unix time at midnight UTC of that date, seconds
to: With ?to= only: the other date, normalized ISO
days: With ?to= only: signed days from the date to ?to=. Future positive, past negative

Deep fields

deep.year: Year
deep.month: Month, 1 to 12
deep.month_name: English month name
deep.day: Day of month
deep.weekday: ISO weekday, Monday 1 to Sunday 7
deep.weekday_name: English weekday name
deep.week: ISO 8601 week number
deep.week_year: The year that ISO week belongs to. Differs from year around January 1
deep.day_of_year: Day of year, 1 to 366
deep.quarter: Quarter, 1 to 4
deep.leap: Whether the year is a leap year
deep.days_in_month: Days in that month

Build with Date

All tutorials →

QUESTIONS

When do I use which?: Pass the date to parse it. Add to= to count days between two dates. Bare /date?to= counts from today.
What formats parse?: ISO, spelled months in both orders (March 29, 2026 and 29 Aug 2026), numeric like 3/29/2026, and compact 20260829. A leading weekday and an ISO time tail are ignored.
What about 03/04/2026?: March 4th or April 3rd, both are real days, so it answers valid: false. Pass format=mdy or format=dmy to assert a reading. 3/29/2026 resolves on its own, since 29 cannot be a month. We never guess.
How do I count days between dates?: Add to=. /date/2026-08-29?to=2026-12-25 appends to and days: 118. Signed, so a past date goes negative. Bare /date?to= counts from today.
What week numbering is this?: Add deep=true for calendar detail on every plan. deep.week and deep.week_year use ISO 8601: weeks start Monday, and the week-year can differ from the calendar year near January 1.
What counts as junk?: Anything that does not resolve to one real calendar day, including two-digit years. Junk answers valid: false as a 200, never a 404.

Count workdays between dates in the business days calculator. Choose your calendar and which dates to include.

Dates that make sense.

Parse, format, and compare dates. Every plan.

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