ForHosting KIT · Developer Utilities

Days elapsed in the year

This days-elapsed-in-the-year calculator takes one Gregorian calendar date in strict YYYY-MM-DD form and returns how many whole days have already passed since January 1 of that same year.

● BetaFree · in your browser
Use it from WebAPIEmailTelegramApp soon

Classic checks include 2024-01-01 yielding zero days elapsed, 2024-03-15 yielding seventy-four days in a leap year, and 2023-12-31 yielding three hundred sixty-four days in a common year. The engine uses only deterministic proleptic Gregorian arithmetic: it validates that the day actually exists on the calendar, sums the lengths of the months before the given month, adds the day-of-month, then subtracts one so January 1 is zero rather than one. There are no network calls, no random sampling, and no dependence on the host clock or Date object. Use it free in the browser for planning, progress trackers, and homework, or call the API at $0.002 per successful request when you need reproducible day-of-year fixtures in CI, reporting pipelines, or product features.

How to use it

Enter your values in the form above. The tool checks them before calculating and shows the result on the same page.

Check your inputs

Use the labels and units shown next to each field. If something is missing or outside the allowed range, the page points to the field to fix.

Use it again or automate it

Use the browser tool for individual checks and the API when you need the same capability in an automated workflow.

Get an answer now

Enter one set of values and see the result without building a spreadsheet or script.

Compare scenarios

Change one value at a time and rerun the calculation to understand what affects the result.

Automate repeated work

Use the API when the same calculation needs to run inside your product or workflow.

How do I use this capability?

Complete the fields above and run it on this page. The form highlights anything that needs attention.

Everything on this page is available programmatically. This section is for teams who want to wire it into their own systems; everyone else can just use the tool above.

POSThttps://api.kit.forhosting.com/date/days-elapsed-year

Prefer to automate it? One authenticated POST creates the task; the result comes back by webhook or a signed link. The same capability also runs here on the web, by email and from Telegram — and soon from our app too.

curl -X POST https://api.kit.forhosting.com/date/days-elapsed-year \
  -H "Authorization: Bearer $KIT_KEY" \
  -H "Content-Type: application/json" \
  -d '{"date":"2024-03-15"}'
{
  "date": "2024-03-15"
}
{
  "task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
  "type": "date.days_elapsed_year",
  "status": "queued",
  "_links": {
    "result": "/tasks/tsk_…/result"
  }
}

The API is asynchronous: the call returns a task_id immediately and the result arrives by webhook. Polling is capped at 1 req/s per task.

Per request$0.002

Published price — no tokens, no invented credits. A failed task is never charged.

year_min1
year_max9999
HTTPCodeMeaning
401unauthorizedMissing or invalid API key.
402insufficient_balanceYour balance doesn't cover the task price.
404unknown_typeThat task type doesn't exist.
429rate_limitedToo many requests. Use the webhook instead of polling.

Read the full KIT documentation →