Teaspoons to ml converter
One US teaspoon is 4.92892159375 ml, about 4.93, while a metric teaspoon is exactly 5 ml, so 3 metric teaspoons make 15 ml. Choose the teaspoon size and the direction, enter the amount and get the exact conversion. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Amount
- 1
- Conversion direction
- tsp_to_ml
- Result
- 4.9289215938
- Standard
- us
- From unit
- tsp
- To unit
- ml
This teaspoons to milliliters converter turns kitchen volumes between teaspoons and milliliters using the two teaspoon sizes cooks actually meet: the US customary teaspoon of 4.92892159375 milliliters and the metric teaspoon of exactly five milliliters. Enter a non-negative amount, choose direction (teaspoons to milliliters or milliliters to teaspoons), and optionally pick the standard; the engine scales with a fixed factor and returns the result with the factor and unit labels. Small checks include one US teaspoon equaling about 4.93 milliliters and three metric teaspoons equaling fifteen milliliters.
What the converter returns and which teaspoon standards it uses
A teaspoon is not a single universal volume. US recipes, measuring spoons sold in the United States, and many classic cookbooks treat one teaspoon as one sixth of a US fluid ounce, which is exactly 4.92892159375 milliliters. Nutrition labels, many international baking formulas, and metric kitchen sets instead define one teaspoon as five milliliters flat.
Mixing those conventions is a common source of off-by-a-few-percent errors when a European formula is scaled with American spoons or when a diet tracking app assumes five milliliters while the user measures with a US set. This tool makes the choice explicit: standard us applies the NIST-consistent US fluid factor, and standard metric applies five milliliters per teaspoon. There is no density conversion, no weight of sugar or flour, and no tablespoon or cup path: those belong on dedicated pages.
Invalid cases include a missing amount or direction, non-finite numbers, amounts above the documented ceiling, unknown direction or standard tokens, and any negative amount, because a kitchen volume cannot be negative.
Where teaspoon and milliliter conversion fits in cooking and software
Home cooks meet this conversion when a US family recipe lists half a teaspoon of vanilla and a metric measuring jug only shows milliliters, or when a European cake formula in milliliters must be followed with American measuring spoons. Meal-prep and nutrition apps convert small liquid additions so diary entries stay consistent whether the user typed teaspoons or milliliters. Teachers and culinary students use fixed factors for worksheet keys without trusting opaque calculator apps that silently switch between four point nine and five milliliters.
Product teams call the same contract from scripts to seed deterministic test vectors for recipe importers, to normalize user-entered tsp and ml fields before scaling a batch, or to satisfy programming-challenge statements that demand a documented US or metric factor rather than a hand-waved five.
What you can do with it
Recipe adaptation US ↔ metric
Convert teaspoon measures in family recipes to milliliters (or back) using the correct US or metric teaspoon size.
Nutrition and meal-prep apps
Normalize small liquid amounts between tsp and ml so diary totals and labels stay consistent across locales.
FAQ
What does the teaspoons to ml converter cost?
It is free in your browser on this page.
How many milliliters are in one teaspoon?
US customary: 4.92892159375 mL per teaspoon. Metric: exactly 5 mL per teaspoon. Choose standard us or metric.
Does this convert tablespoons or cups?
No. It only converts teaspoons and milliliters under the chosen standard. Use a dedicated volume tool for other kitchen units.
Should I use the US or the metric teaspoon?
Use the US teaspoon for American recipes and measuring spoons sold in the United States. Use the metric teaspoon of 5 ml for nutrition labels, many international baking formulas and metric kitchen sets.
Can I convert milliliters to teaspoons?
Yes. Choose the direction from milliliters to teaspoons and the converter divides by the factor of the teaspoon size you picked. It helps when a European formula in milliliters must be followed with spoons.
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/tsp-ml \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"amount":1,"direction":"tsp_to_ml"}'const res = await fetch("https://api.kit.forhosting.com/cook/tsp-ml", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"amount": 1,
"direction": "tsp_to_ml"
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/cook/tsp-ml",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"amount": 1,
"direction": "tsp_to_ml"
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/cook/tsp-ml", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"amount":1,"direction":"tsp_to_ml"}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"amount":1,"direction":"tsp_to_ml"}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/cook/tsp-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": 1,
"direction": "tsp_to_ml"
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "cook.tsp_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.
Limits
max_abs_amount | 1000000000000 |
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
Use it free in the browser while adapting family recipes, or call the API at $0.002 per successful request when your app must convert tsp and ml without re-implementing the factors.
What the converter returns and which teaspoon standards it uses
You send amount and direction, and the response echoes the normalized amount, the canonical direction and standard, the numeric result, from_unit and to_unit strings, the ml_per_tsp factor used, a short standard_label, the precision applied, a method tag, and a formula reminder. If validation fails you get invalid_input with a clear message and the request is not charged.
How amount, direction, and standard are read so results stay reproducible
Optional leading plus signs and scientific notation on amount strings are accepted when they parse as finite decimals; embedded spaces, hex prefixes, and non-numeric tokens are rejected so a bad cell does not become a silent wrong volume. Zero amount is valid and returns zero in the target unit. The preferred fields are amount for the magnitude, direction for tsp_to_ml or ml_to_tsp, and optional standard for us or metric. Aliases such as value, quantity, n, and qty map to amount; dir, convert, mode, and way map to direction; tsp_standard, system, size, and convention map to standard, so spreadsheets, query strings, and typed forms can reuse the same contract without renaming columns. Direction aliases include tsp2ml, to_ml, teaspoons_to_ml, ml2tsp, and milliliters_to_teaspoons; standard aliases include usa, american, si, iso, and nutrition for the five-milliliter convention. An optional precision field, with aliases decimals and dp, chooses how many decimal places to expose for amount, result, and ml_per_tsp, defaulting to ten and capped at fifteen so JSON goldens stay stable across runs. Pair the free browser run on this page with the priced API when you need the identical mathematical result inside an automated pipeline without re-implementing the teaspoon factors yourself.
Where teaspoon and milliliter conversion fits in cooking and software
On this page the work runs entirely in your browser; through the API each successful lookup costs $0.002, failed validation is not charged, and nothing is stored after the response returns. That split — free interactive exploration and a priced, identical API — matches the rest of the KIT tier-A catalog and lets you move from a kitchen demo to an automated pipeline without changing the mathematical result. Pair it with broader unit tools when you need cups or grams, and keep this endpoint when the search intent is specifically teaspoons to milliliters with an explicit US versus metric choice.
Integration use cases
Deterministic test fixtures
Generate reproducible tsp↔ml results for unit tests, recipe importers, and CI assertions without re-coding factors.
Technical questions
What happens if the amount is negative?
The input is rejected with invalid_input. Teaspoon and milliliter volumes must be non-negative.
Can I convert milliliters back to teaspoons?
Yes. Set direction to ml_to_tsp (aliases such as ml2tsp and to_tsp are accepted) and provide the milliliter amount.