Height in inches converter
Five feet eleven is 71 inches and six feet even is 72: the feet are multiplied by 12 and the remaining inches added. Get the single total that a BMI sheet, a growth chart or a licence form wants. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Feet
- 5
- Inches
- 11
- Result
- 71 in
- Total inches
- 71
- Inches per foot
- 12
A height in inches converter turns the everyday feet-and-inches reading used on US medical charts, driver's licenses, clothing size tables, and school health records into a single total-inch count that spreadsheets, BMI formulas, and growth-chart APIs actually consume. Enter a non-negative finite number of feet and a non-negative finite number of inches; the tool multiplies feet by the exact definition that one foot equals twelve inches, adds the remaining inches, and returns the total inch count together with the echoed inputs, the formula, and ordered substitution steps you can paste into a worksheet.
Why mixed feet and inches still collapse to a total inch count
US clinics, clothing brands, school nurses, and many government forms still collect standing height as mixed feet and inches, then store or score it as a single integer inch count. Body-mass index worksheets, pediatric growth charts, driver's-license databases, and apparel size engines expect that total, not a two-part string such as five-foot-eleven. The conversion is not an approximation: by definition one international foot equals exactly twelve inches, so total inches equals feet times twelve plus the remaining inches.
A person recorded as five feet eleven inches is therefore seventy-one inches; six feet even is seventy-two inches; zero feet and zero inches is zero. This capability never applies survey-foot variants, never wraps extra inches modulo twelve, and never guesses when a field is missing. Teachers still teach mixed feet-and-inches display, but the stored magnitude must stay exact so a seventy-one-inch chart always matches five-foot-eleven on paper.
Negative feet or inches are rejected because a height is a non-negative stature, not a signed length delta.
Practical tips, checks, and related searches
Prefer sending bare numbers when you control the client; string numbers are accepted only when they match a strict finite numeric pattern without units, apostrophes, or quotation marks. Round-trip sanity checks are easy: convert the textbook height five feet eleven inches and confirm you receive exactly seventy-one inches after rounding, or convert six feet and zero inches and confirm exactly seventy-two inches. When teaching, pair the exact path with mixed feet-and-inches display so students see how remainder inches relate to the stored total.
Stay with non-negative finite values so the multiply-add cannot overflow into a non-finite result the solver must reject. This landing targets people searching for height in inches, convert feet and inches to inches, or a five-foot-eleven to inches calculator; it is not a general multi-unit length hub, not a centimetres-to-inches primary form, not a BMI calculator, and not a split-back mixed-unit formatter.
Prefer this capability when the input is already feet plus inches and you only need the total inch count; if you must convert among many length units in one call, use a broader unit converter instead.
What you can do with it
Clinic charts and BMI worksheets
Turn a nurse's five-foot-eleven tape reading into seventy-one inches so BMI, growth-chart, and EHR fields that store stature as integer inches stay exact.
Apparel size charts and product specs
Merchants convert mixed feet-and-inches height bands to total inches before publishing size tables, so shoppers and warehouse sheets share one magnitude.
FAQ
How do I convert height in feet and inches to total inches?
Send non-negative finite numbers feet and inches. Five feet eleven inches returns 71.
Is the twelve-inches-per-foot factor exact?
Yes. One international foot is defined as exactly twelve inches. This tool does not use survey-foot variants or mental shortcuts.
What if inches is 12 or more?
Values of 12 or more are added in full. Six feet fourteen inches is 86 inches, not wrapped to seven feet two inches.
Is the height in inches converter free?
The browser tool is free and runs locally.
Can I type 5'11 with the apostrophe?
No. Enter the feet and the inches as two separate numbers, 5 and 11. Apostrophes, quotation marks, unit letters and mixed text are rejected so a height is never misread.
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/conv/height-in-inches \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"feet":5,"inches":11}'const res = await fetch("https://api.kit.forhosting.com/conv/height-in-inches", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"feet": 5,
"inches": 11
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/conv/height-in-inches",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"feet": 5,
"inches": 11
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/conv/height-in-inches", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"feet":5,"inches":11}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"feet":5,"inches":11}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/conv/height-in-inches", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"feet": 5,
"inches": 11
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "conv.height_in_inches",
"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
Negative feet or inches, missing fields, and non-finite values fail with invalid_input instead of inventing a stature.
Why mixed feet and inches still collapse to a total inch count
Non-finite values, empty strings, and bare plus or minus signs fail with invalid_input instead of a silent zero.
How to call the API and what comes back
String numbers that match a strict finite numeric pattern are coerced; unit suffixes, thousand separators, and mixed strings such as five-foot-eleven are rejected. Inch values of twelve or more are added in full rather than wrapped, which keeps the identity honest when a caller already stored leftover inches above eleven. Send a JSON body with two required non-negative finite numbers: feet, the whole-foot part of the height, and inches, the remaining inches. Aliases ft, foot, and height_feet are accepted for the first field; in, inch, and height_inches are accepted for the second so SDK clients and form posts can use the name that fits the product. On success the response echoes rounded feet and inches, sets total_inches and result to the same rounded total inch count, unit to the token in, inches_per_foot to the exact constant twelve, formula to the string total inches equals feet times twelve plus inches, message to a short English summary, and steps to an ordered array of substitution lines. Failed validation—missing fields, non-finite numbers, negative values, or a non-finite converted result—returns invalid_input and is never charged. Pricing is a flat $0.002 per successful request with unit item.
Practical tips, checks, and related searches
Failed tasks that return invalid_input do not consume prepaid balance, which keeps exploratory scripts cheap when learners deliberately omit feet or pass a negative remainder.
Integration use cases
Homework and unit-test fixtures
Students and engineers convert classroom height readings to total inches and pin golden JSON so browser and API arithmetic never drift.
Technical questions
What happens on negative or missing input?
The API returns invalid_input naming the problem (for example a negative feet field). Failed tasks are not charged.