Fluid ounces to ml converter
Eight US fluid ounces are 236.5882365 ml, while one imperial fluid ounce is 28.4130625 ml, about 4% smaller than the US one. Choose the system and the direction, enter any amount, and get the result with the exact factor used. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Volume magnitude to convert
- 8
- Fluid-ounce definition: us
- Us
- Conversion direction: fl_oz_to_ml
- Fl oz to ml
- Result
- 236.5882365
- From unit
- fl_oz
- To unit
- ml
- Factor ml per fl oz
- 29.5735295625
Recipes, beverage labels, and barware rarely agree on which fluid ounce they mean. American cookbooks and nutrition panels use the US customary fluid ounce while many UK and Commonwealth sources still write imperial fluid ounces, and the two sizes differ by roughly four percent. This fluid ounces to ml converter multiplies or divides your amount by the exact system factor—twenty-nine point five seven three five two nine five six two five milliliters for each US fluid ounce, or twenty-eight point four one three zero six two five milliliters for each imperial fluid ounce—so dual-unit recipe cards, cocktail batches, and packaging specs stay consistent. Choose a system, choose a direction, enter any finite amount including fractions, and receive the converted volume plus the factor and formula used. Unknown systems and non-numeric amounts fail with a clear validation error instead of inventing a rounded guess.
How fluid ounces convert to milliliters
A fluid ounce is a unit of volume, not a weight ounce. The US customary fluid ounce is defined from the US gallon of exactly three point seven eight five four one one seven eight four liters with one hundred twenty-eight fluid ounces per gallon, which yields exactly twenty-nine point five seven three five two nine five six two five milliliters per fluid ounce.
The imperial fluid ounce is defined from the imperial gallon of exactly four point five four six zero nine liters with one hundred sixty imperial fluid ounces per gallon, which yields exactly twenty-eight point four one three zero six two five milliliters per fluid ounce. Converting fluid ounces to milliliters is therefore a single multiplication by the factor that matches the system you chose. Converting milliliters back to fluid ounces is the inverse division.
This capability stores both exact factors once and applies them deterministically—no web scrapes, no language-model estimates, no temperature corrections that change between calls. Weight ounces and cups-by-density tools are intentionally out of scope; if you need dry ounces to grams, use a kitchen weight converter instead. When product pages round either fluid ounce to thirty milliliters they introduce small drift on large beverage batches; keeping the full SI-derived constant keeps multi-liter prep sheets honest.
Amounts, systems, and directions are validated first; non-numeric amounts and unknown systems fail with invalid input and are not charged.
Where a fluid ounces to ml converter shows up in real work
Home cooks translating American liquid recipes onto metric measuring jugs avoid the classic eight-ounce-cup confusion when every fluid volume has a published milliliter equivalent for the correct system. Food bloggers and cookbook editors publish dual-unit liquid lines and need one oracle so fluid-ounce lines and milliliter lines never drift between drafts. Cocktail bars and beverage formulators batch syrups and spirits from fluid-ounce written cards into scale-ready milliliters without opening a spreadsheet of ad-hoc rounded constants.
Culinary schools teach unit literacy—why US and imperial fluid ounces differ, and why neither equals a weight ounce—and a deterministic factor makes demos and quizzes reproducible. Small producers writing nutrition and net-content labels convert consumer-facing fluid ounces into milliliters required by metric markets. Meal-prep services and grocery apps convert user-entered fluid-ounce quantities into purchase milliliters for shopping lists and cost estimates.
If you later need multi-unit kitchen chains across cups and tablespoons, weight ounces to grams, or a general unit picker with a different search intent, treat those as separate landings rather than overloading this fluid-ounces-to-milliliters converter page.
What you can do with it
Scale a liquid recipe to metric
Turn 8 US fl oz of stock or milk into milliliters so a metric jug matches the written fluid-ounce recipe without guesswork.
Dual-unit beverage publishing
Editors and bloggers generate consistent milliliter lines beside fluid-ounce lines from one exact US or imperial factor for every liquid.
Cocktail and bar batching
Convert fluid-ounce bar cards into milliliters for bottle prep, cost sheets, and metric jiggers before service.
FAQ
How does the fluid ounces to ml converter work?
It multiplies fluid ounces by 29.5735295625 ml (US) or 28.4130625 ml (imperial) to get milliliters, or divides milliliters by the same factor to get fluid ounces. You choose the system.
Is this fluid ounces or weight ounces?
Fluid (volume) ounces only. Weight avoirdupois ounces measure mass and are out of scope for this converter.
Why do US and imperial fluid ounces differ?
They are defined from different gallons: the US gallon is 3.785411784 L with 128 fl oz, while the imperial gallon is 4.54609 L with 160 fl oz.
What does it cost?
The browser tool is free and runs locally.
Why not just round a fluid ounce to thirty milliliters?
Because the small error grows on big batches. A US fluid ounce is exactly 29.5735295625 ml, and using the full factor keeps multi-liter drink and stock prep sheets accurate instead of drifting a little with every ounce.
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/fl-oz-ml \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"amount":8,"system":"us","direction":"fl_oz_to_ml"}'const res = await fetch("https://api.kit.forhosting.com/cook/fl-oz-ml", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"amount": 8,
"system": "us",
"direction": "fl_oz_to_ml"
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/cook/fl-oz-ml",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"amount": 8,
"system": "us",
"direction": "fl_oz_to_ml"
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/cook/fl-oz-ml", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"amount":8,"system":"us","direction":"fl_oz_to_ml"}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"amount":8,"system":"us","direction":"fl_oz_to_ml"}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/cook/fl-oz-ml", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"amount": 8,
"system": "us",
"direction": "fl_oz_to_ml"
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "cook.fl_oz_ml",
"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
What you send and what you get back
Classic kitchen checks include eight US fluid ounces of stock becoming two hundred thirty-six point five eight eight two three six five milliliters, one hundred milliliters becoming about three point three eight one four zero two two seven imperial fluid ounces, and one US fluid ounce mapping exactly to twenty-nine point five seven three five two nine five six two five milliliters. Use the free browser form while scaling a single recipe on the counter, then call the same contract from scripts when you generate dual-unit cards or import supplier packs marked only in fluid ounces. Wire the returned result into meal-planning tools, label printers, and beverage calculators that already work in milliliters. Send three fields. amount is a finite number of volume units—eight, one half, twelve point five, or any other finite value including negatives if you are modeling a delta. system is either us for the US customary fluid ounce or imperial for the UK imperial fluid ounce; matching is case-insensitive and accepts everyday aliases such as usa, uk, and imp. direction is either fl_oz_to_ml for fluid ounces to milliliters or ml_to_fl_oz for milliliters to fluid ounces; aliases such as fluid_ounces_to_ml and ml-to-floz are accepted. Missing fields, non-numeric strings, empty strings, NaN, Infinity, unknown systems, and directions outside the accepted set fail with invalid_input and are not charged. On success the response echoes the cleaned amount, the canonical system and direction, from_unit and to_unit as fl_oz or ml, result as the converted magnitude, factor_ml_per_fl_oz for the chosen system, a printable formula string, and method us_fluid_ounce_exact or imperial_fluid_ounce_exact. Pricing for successful API calls is the published base of $0.002 per item; validation failures do not consume prepaid balance.
Where a fluid ounces to ml converter shows up in real work
Because this capability is a pure parse engine, API pricing is the published base of $0.002 per successful item and failed validation does not consume balance.
Technical questions
What happens if the system is unknown?
The request fails with invalid_input. Only us and imperial (and listed aliases) are accepted; other system strings are rejected and the call is not charged.