ForHosting KIT · Developer Utilities

Center of an ellipse

Center of an ellipse: enter your values and see a clear result on this page. Free for individual checks; API from $0.002.

● BetaFree · in your browser

Run — free How it works & API

Use it from WebAPIEmailTelegramApp soon

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.

What you can do with it

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.

FAQ

What does it cost?

$0.002 per request. The same solver also runs free in your browser on this page.

Which equation form does it accept?

The general conic Ax^2 + Bxy + Cy^2 + Dx + Ey + F = 0. A, C and F are required; B, D and E default to zero when omitted.

How is the center computed?

By solving the stationary-point system 2Ah + Bk = −D and Bh + 2Ck = −E, giving h = (BE − 2CD)/(4AC − B^2) and k = (BD − 2AE)/(4AC − B^2).

What happens if the equation is not an ellipse?

You get an invalid_input error. The discriminant B^2 − 4AC must be negative, and degenerate (single-point) or imaginary ellipses are also rejected with a message that says which case it is.

Does it work with rotated ellipses?

Yes. A non-zero B coefficient (the xy term) indicates rotation and is handled by the same formulas; no special mode is needed.

Is anything stored?

No. The coefficients are processed and discarded; only the center coordinates and the diagnostic fields are returned.

For developers — API access

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.

API endpoint

POSThttps://api.kit.forhosting.com/math/center-of-ellipse

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.

Call it from your stack

curl -X POST https://api.kit.forhosting.com/math/center-of-ellipse \
  -H "Authorization: Bearer $KIT_KEY" \
  -H "Content-Type: application/json" \
  -d '{"a":4,"c":9,"f":-36}'

const res = await fetch("https://api.kit.forhosting.com/math/center-of-ellipse", {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${process.env.KIT_KEY}`,
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    "a": 4,
    "c": 9,
    "f": -36
  })
});
const { task_id } = await res.json();

import os, requests

res = requests.post(
    "https://api.kit.forhosting.com/math/center-of-ellipse",
    headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
    json={
    "a": 4,
    "c": 9,
    "f": -36
},
)
task_id = res.json()["task_id"]

<?php
$res = file_get_contents("https://api.kit.forhosting.com/math/center-of-ellipse", false, stream_context_create([
  "http" => [
    "method"  => "POST",
    "header"  => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
    "content" => '{"a":4,"c":9,"f":-36}',
  ],
]));
$task = json_decode($res, true);

body := bytes.NewBufferString(`{"a":4,"c":9,"f":-36}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/math/center-of-ellipse", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)

Example request

{
  "a": 4,
  "c": 9,
  "f": -36
}

Example response

{
  "task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
  "type": "math.center_of_ellipse",
  "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.

Pricing

Per request$0.002

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

Errors

HTTP	Code	Meaning
`401`	`unauthorized`	Missing or invalid API key.
`402`	`insufficient_balance`	Your balance doesn't cover the task price.
`404`	`unknown_type`	That task type doesn't exist.
`429`	`rate_limited`	Too many requests. Use the webhook instead of polling.

Read the full KIT documentation →