Tablespoons to Milliliters Converter
Convert US tablespoons to milliliters — and spot the 20 mL Australian tablespoon.
Updated
milliliters
14.79mL
1 tbsp = 14.79 mL
In short
How many mL is a tablespoon?
One US tablespoon is 14.79 millilitres, from the exact figure 14.78676478125. The metric tablespoon used across the UK and Europe is a round 15, only 1.44 percent larger. The Australian tablespoon is the outlier at 20 millilitres, which is 35.26 percent larger and equals four teaspoons rather than three.
Two US tablespoons make exactly one fluid ounce, which is why 29.57 mL keeps appearing on drink recipes.
US tablespoons to milliliters — quick reference
| US tablespoons (tbsp) | milliliters (mL) |
|---|---|
| 0.5 tbsp | 7.39 mL |
| 1 tbsp | 14.79 mL |
| 1.5 tbsp | 22.18 mL |
| 2 tbsp | 29.57 mL |
| 3 tbsp | 44.36 mL |
| 4 tbsp | 59.15 mL |
| 6 tbsp | 88.72 mL |
| 8 tbsp | 118.29 mL |
The formula, worked line by line
The conversion multiplies by a constant that was defined rather than measured. A US tablespoon is half a US fluid ounce, the fluid ounce is a hundred and twenty-eighth of the US liquid gallon, and the gallon is exactly 231 cubic inches. Fix the inch at 2.54 centimetres and the whole chain becomes exact.
“The US gallon is exactly 231 cubic inches, and the inch is exactly 2.54 centimetres.”
Because every step is exact, the arithmetic adds no error at all. Whatever inaccuracy reaches the pan comes from how level the spoon was, which is a much larger and much less discussed source of variation than the choice between 14.79 and 15.
mL = US tbsp x 14.78676478125
14.78676478125 = 29.5735295625 / 2 (half a fluid ounce)
1 tbsp -> 1 x 14.78676478125 = 14.79 mL
2 tbsp = 1 fl oz - 16 tbsp = 1 cup - 3 tsp = 1 tbsp
metric spoon: mL = spoons x 15 - Australian: mL = spoons x 20- Tablespoons entered
- 1
- Exact factor
- 14.78676478125 mL per tablespoon
- Multiplication
- 1 x 14.78676478125 = 14.78676478125
- Millilitres
- 14.79 mL
Against the metric 15 millilitre spoon that is a shortfall of 0.21 millilitres, or 1.44 percent. It is roughly four drops, and less than the film of oil or batter that stays on the spoon after tipping it, which is why nobody has ever needed to own both spoons.
The 15 mL shortcut, measured
Treating a US tablespoon as 15 millilitres runs 1.44 percent high and always in the same direction, so it accumulates rather than cancelling. At one spoonful it is four drops. At sixteen spoonfuls, which is a full cup, it reaches 3.41 millilitres, or roughly a quarter of an extra tablespoon.
- At 1 tbsp
- 0.21 mL over, invisible
- At 4 tbsp, a quarter cup
- 0.85 mL over
- At 8 tbsp, a half cup
- 1.71 mL over
- At 16 tbsp, one cup
- 3.41 mL over
By the time the error is visible, the sensible instrument is a measuring cup rather than sixteen separate spoonfuls, which is why the shortcut survives.
Two tablespoons is exactly one fluid ounce
This is the most useful ratio on the page and the least advertised. A fluid ounce is two tablespoons, so a drink recipe in fluid ounces can be measured with a spoon and one in tablespoons can be scaled with a jigger. A standard 1.5 fluid ounce jigger is three tablespoons, or 44.36 millilitres.
How to use the tablespoons to milliliters converter
A US tablespoon is 14.78676478125 millilitres, which displays as 14.79. It is half a fluid ounce exactly, and the fluid ounce is a US gallon of 231 cubic inches split into 128 parts. That is why the decimal is long and why it terminates: every step in the chain is a definition rather than a measurement.
For everyday cooking the number that matters is 15. The metric tablespoon sold across the UK and most of Europe is a round 15 millilitres, 1.44 percent more than the US one. On a single spoonful that is about two tenths of a millilitre, which is less than what stays behind on the spoon when you tip it.
14.79 mL
One US tablespoon
exactly 14.78676478125
15 mL
The metric tablespoon
UK and most of Europe
20 mL
The Australian tablespoon
35.26 percent larger
The Australian spoon is the one that will actually change a dish. At 20 millilitres it holds four metric teaspoons rather than three, so a recipe from Australia asking for three tablespoons of oil means 60 millilitres where an American reading gives 44. That is half a fluid ounce of difference in a dressing.
The other useful anchor is the fluid ounce. Two US tablespoons make exactly one fluid ounce, or 29.57 millilitres, which is why so many drink recipes are written in even numbers of tablespoons. Sixteen tablespoons make a cup, so a quarter cup is four tablespoons and a half cup is eight.
- 0.5 tbsp
- 7.39 mL
- 1 tbsp, three teaspoons
- 14.79 mL
- 2 tbsp, one fluid ounce
- 29.57 mL
- 4 tbsp, a quarter cup
- 59.15 mL
- 8 tbsp, a half cup
- 118.29 mL
- 16 tbsp, one cup
- 236.59 mL
Every rung is a whole multiple of the tablespoon, so a recipe written in spoons scales into cups without any awkward arithmetic.
When the quantity is smaller than a spoonful
Three teaspoons make a tablespoon, and below half a tablespoon the smaller spoon measures far more reliably. That page uses the exact 4.92892159375 millilitre teaspoon.
Open the teaspoon converter →US tablespoons converted to millilitres, with the metric 15 mL spoon and the Australian 20 mL spoon alongside for the same count of spoonfuls.
| Spoonfuls | US tablespoons | Australian, at 20 mL |
|---|---|---|
| 0.5 | 7.39 mL | 10 mL |
| 1 | 14.79 mL | 20 mL |
| 1.5 | 22.18 mL | 30 mL |
| 2 | 29.57 mL | 40 mL |
| 3 | 44.36 mL | 60 mL |
| 4 | 59.15 mL | 80 mL |
| 5 | 73.93 mL | 100 mL |
| 6 | 88.72 mL | 120 mL |
| 8 | 118.29 mL | 160 mL |
| 10 | 147.87 mL | 200 mL |
| 12 | 177.44 mL | 240 mL |
| 16 | 236.59 mL | 320 mL |
| 32 | 473.18 mL | 640 mL |
The Australian tablespoon is a real problem
Most international measuring differences are roundings that vanish in practice. This one does not. Standards Australia specifies a 20 millilitre tablespoon, while New Zealand government material and British convention both use 15. A recipe crossing that border carries a 35.26 percent error on every tablespoon in it.
Where it shows first is anything where the spoon is doing structural work rather than seasoning. Three tablespoons of flour in a roux, of oil in a dressing, or of liquid in a small batter are quantities the dish depends on. A third more of any of them is not a nuance, it is a different recipe.
- Three US tablespoons
- 44.36 mL
- Three metric tablespoons
- 45 mL
- Three Australian tablespoons
- 60 mL
- Australian against US
- 15.6 mL more, over half a fluid ounce
- US and metric
- interchangeable; Australian is not
The US and metric spoons differ by 0.64 millilitres across three spoonfuls, which is a few drops. The Australian spoon adds more than a full extra US tablespoon over the same three. One of these is a rounding question and the other is a substitution error.
The safe habit is to check the recipe source before scaling anything measured in tablespoons. Where a recipe gives metric figures alongside its spoons, those settle the question immediately: a tablespoon printed as 20 mL tells you everything, and one printed as 15 mL tells you the rest.
Why 14.79 refuses to be 15
The US tablespoon was never defined against the millilitre. It is half a fluid ounce, the fluid ounce is one hundred and twenty-eighth of the US liquid gallon, and that gallon is exactly 231 cubic inches. Only in 1959, when the inch was fixed at 2.54 centimetres, did the whole chain become exactly expressible in metric.
The metric tablespoon went the other way. It was chosen to be 15 millilitres because that is a convenient number, not derived from anything older. The two landed 1.44 percent apart by coincidence, close enough that no kitchen has ever had to pick a side and far enough that the decimal never tidies up.
- US liquid gallon
- 231 cubic inches, exactly
- In litres, once the inch is 2.54 cm
- 3.785411784 L
- Divided by 128, the fluid ounce
- 29.5735295625 mL
- Divided by 2, the tablespoon
- 14.78676478125 mL
A terminating decimal is the signature of an exact definition. A repeating one would have meant the relationship was measured rather than declared.
The FDA uses a third figure again. For nutrition labelling it defines a tablespoon as 15 millilitres, a teaspoon as 5 and a fluid ounce as 30, all deliberate roundings for packaging rather than conversions of the customary units. That is why a label and a recipe can disagree slightly without either being wrong.
Every US tablespoons value, worked out
29 common US tablespoons figures each get their own page, with the answer at full precision, the arithmetic, what rounding costs, and the nearest real-world reference point on the scale.
Questions people ask
Sources
Where the constants and formulas on this page come from. Each line names the figure it backs.
The US tablespoon is half the US fluid ounce of exactly 29.5735295625 millilitres, giving 14.78676478125 mL.
NIST Guide to the SI, Appendix B.8 — Factors for units listed alphabetically — NIST
The Australian tablespoon is specified as 20 mL, unlike the 15 mL spoon used in New Zealand and most of the rest of the world.
AS 1325 — Kitchen utensils for measuring food ingredients — Standards Australia
For nutrition labelling the FDA defines a tablespoon as 15 mL, a teaspoon as 5 mL and a fluid ounce as 30 mL.
21 CFR 101.9(b)(5)(viii) — Nutrition labeling of food — US Food and Drug Administration, via the eCFR
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