Celsius to Gas Mark Converter
A recipe at 176 °C becomes Gas Mark 4, the dial setting closest to it at 180 °C. Enter a Celsius temperature from 110 to 240 and get the nearest gas mark, how far it sits from your figure and whether it matches exactly. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Celsius
- 175
- Gas mark
- 4
- Gas mark label
- Gas Mark 4
- Matched celsius
- 180
- Difference celsius
- 5
This Celsius to gas mark converter finds the nearest traditional British oven setting for a temperature between 110 and 240 degrees Celsius. It uses a fixed eleven-row lookup table rather than an approximate formula, so the same input always produces the same result. The response shows the selected gas mark, its table temperature, the distance from your original temperature, and whether the match was exact. Temperatures outside the supported range return a clear input error. It is useful for adapting metric recipes to older British gas ovens, checking cookbook instructions, and building predictable recipe software without network calls or changing reference data.
How the Celsius lookup works
British gas marks are discrete oven settings, while Celsius is a continuous temperature scale. This converter therefore compares the supplied Celsius value with every temperature in a fixed British cooking table. The table maps Gas Mark one-quarter to 110 °C, one-half to 120 °C, and marks one through nine to 140, 150, 160, 180, 190, 200, 220, 230, and 240 °C.
The entry with the smallest absolute temperature difference is selected. For example, 176 °C is four degrees from 180 °C and sixteen degrees from 160 °C, so the result is Gas Mark 4. A value of 185 °C is equally close to Gas Mark 4 at 180 °C and Gas Mark 5 at 190 °C.
Exact ties deliberately choose the lower-temperature entry, so 185 °C becomes Gas Mark 4. This documented rule avoids an arbitrary or platform-dependent result. No interpolation is performed because a gas mark is a named dial setting, not a fractional temperature unit.
Using the result in real cooking
Use the returned gas mark as the nearest conventional setting on a British gas oven, then apply normal recipe judgment. Oven thermostats vary, older appliances can run hot or cool, and fan-assisted ovens often require a separate adjustment that this lookup does not calculate. If the original recipe gives 175 °C, the nearest table setting is Gas Mark 4 at 180 °C, only five degrees higher.
That small difference is usually more useful than inventing a nonexistent half-step on a dial labeled with whole gas marks. For reproducible tests, include exact matches, ordinary nearest matches, a midpoint such as 170 °C that demonstrates lower-temperature tie-breaking, and an out-of-range value.
What you can do with it
Adapt metric recipes for a gas oven
Turn a Celsius baking instruction into the nearest labeled setting on a traditional British gas oven dial.
Normalize imported recipe data
Add a deterministic gas-mark field to recipes that store conventional oven temperatures in Celsius.
FAQ
What gas mark is 180 degrees Celsius?
180 °C is an exact match for Gas Mark 4 in the fixed table.
What gas mark is 175 degrees Celsius?
175 °C maps to Gas Mark 4, whose table temperature is 180 °C, a difference of 5 °C.
How are halfway temperatures handled?
When two table entries are equally near, the lower-temperature gas mark wins. For example, 170 °C maps to Gas Mark 3 at 160 °C.
Does this converter adjust for fan ovens?
No. It selects the nearest British gas mark from a conventional fixed table; fan-oven offsets and appliance calibration are separate considerations.
What temperature range can I convert?
From 110 °C, which is Gas Mark 1/4, up to 240 °C, which is Gas Mark 9. A temperature outside that range returns an error instead of being quietly moved to the nearest end of the table.
Related tools
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
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/cook/celsius-to-gas-mark \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"celsius":175}'const res = await fetch("https://api.kit.forhosting.com/cook/celsius-to-gas-mark", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"celsius": 175
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/cook/celsius-to-gas-mark",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"celsius": 175
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/cook/celsius-to-gas-mark", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"celsius":175}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"celsius":175}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/cook/celsius-to-gas-mark", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"celsius": 175
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "cook.celsius_to_gas_mark",
"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
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. |
Technical notes
How the Celsius lookup works
The lookup table, scan order, and tie behavior remain fixed for consistent browser, API, test, and recipe-import results.
Input, output, range, and errors
Send one finite number in the celsius field. Valid input starts at 110 °C and ends at 240 °C, inclusive, because those are the lowest and highest entries in this capability’s fixed table. Missing values, numeric strings, infinity, NaN, arrays, and other nonnumeric values are rejected as well. The aliases temperature, temp, and value are also accepted for clients that use a general recipe data model. A number below 110 or above 240 returns invalid_input instead of silently clamping to an endpoint. A successful response preserves the submitted celsius number and returns gas_mark as a canonical string, gas_mark_label as a readable label, matched_celsius as the selected table temperature, and difference_celsius as the absolute distance between the input and match. The exact_match flag is true only when the input itself appears in the table. The tie_break field records the lower-temperature policy so automated clients do not need to infer it. Successful API requests cost $0.002; validation errors are reported before a useful conversion result is produced.
Using the result in real cooking
When the difference_celsius value is larger, consider whether the recipe source expects a fan oven, a conventional oven, or a specialized low-temperature setting before baking. This tool is specifically for Celsius-to-gas-mark selection; it does not convert Fahrenheit, estimate cooking time, compensate for altitude, or judge food safety. Developers can store both the original celsius value and matched_celsius value so users can see that a nearest choice was made.
Integration use cases
Build stable cooking tests
Generate predictable exact, nearest, midpoint, and rejected-range fixtures for cooking applications and forms.
Technical questions
Can I enter a temperature below 110 or above 240 Celsius?
No. Values outside 110–240 °C return invalid_input because they fall outside the fixed lookup table’s supported range.