ForHosting KIT · Developer Utilities

Combined gas law calculator

This combined gas law calculator finds the single missing pressure, volume, or temperature when a fixed amount of ideal gas changes between two states at constant moles.

● BetaFree · in your browser

Run — free How it works & API

Use it from WebAPIEmailTelegramApp soon

The defining relation is P1 times V1 over T1 equals P2 times V2 over T2, which unifies Boyle’s, Charles’s, and Gay-Lussac’s laws into one proportional statement using absolute temperatures. You supply any five of the six state variables and leave the unknown out of the request; the engine rearranges the identity and returns the full set of six values, the name of the variable it solved, and the common P V over T ratio. Temperatures must be absolute—typically kelvin—so zero temperature is rejected as invalid, because division by absolute zero is undefined and has no meaning in this model. Pressures and volumes may use any consistent unit families; the tool never converts atmospheres to pascals or liters to cubic meters for you. The arithmetic is fully deterministic with no network calls, no sampling, and no date-dependent shortcuts. Use it free in the browser for homework, lab prep, and design checks, or call the API at $0.002 per successful request when you need reproducible combined-gas-law fixtures in CI, tutoring software, or teaching demos that must not invent floating-point steps by hand.

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

How do I use this capability?

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

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/thermo/combined-gas-law

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/thermo/combined-gas-law \
  -H "Authorization: Bearer $KIT_KEY" \
  -H "Content-Type: application/json" \
  -d '{"P1":1,"p1":1}'

const res = await fetch("https://api.kit.forhosting.com/thermo/combined-gas-law", {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${process.env.KIT_KEY}`,
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    "P1": 1,
    "p1": 1
  })
});
const { task_id } = await res.json();

import os, requests

res = requests.post(
    "https://api.kit.forhosting.com/thermo/combined-gas-law",
    headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
    json={
    "P1": 1,
    "p1": 1
},
)
task_id = res.json()["task_id"]

<?php
$res = file_get_contents("https://api.kit.forhosting.com/thermo/combined-gas-law", false, stream_context_create([
  "http" => [
    "method"  => "POST",
    "header"  => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
    "content" => '{"P1":1,"p1":1}',
  ],
]));
$task = json_decode($res, true);

body := bytes.NewBufferString(`{"P1":1,"p1":1}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/thermo/combined-gas-law", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)

Example request

{
  "P1": 1,
  "p1": 1
}

Example response

{
  "task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
  "type": "thermo.combined_gas_law",
  "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.

Limits

max_abs_value 1000000000000000

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 →

Run — free