How Much Caffeine Is in Vietnamese Coffee?

Caffeine by dose

The dose is the input you control, and it moves the answer further than roast, variety or brew time do. A phin sized for 120 ml holds about 20 g. Milk-forward drinks and smaller phins use less.

Dose of roasted robusta	Usually means	Caffeine in the dose	ESTIMATE in the cup
8 g	A small phin, barely filled	160–215 mg	130–195 mg
12 g	A bạc xỉu (a milk-forward coffee, southern)	240–325 mg	190–290 mg
15 g	A small phin, filled properly	300–405 mg	240–365 mg
20 g	The standard 120 ml phin, and a cà phê sữa đá (Vietnamese iced coffee with condensed milk)	400–540 mg	320–490 mg
25 g	A generously filled 120 ml phin	500–675 mg	400–610 mg
30 g	A 200 ml phin	600–810 mg	480–730 mg
20 g of arabica instead	The same phin, a Cầu Đất or Sơn La coffee	160–280 mg	130–250 mg

The middle column is what sits in the grounds. The right-hand column is what the published extraction evidence suggests reaches the glass. Both are calculated, and the arithmetic is below.

The arithmetic, shown

We could not find a published measurement of caffeine in a phin brew. So here is the calculation instead, with each input sourced or labelled. Change any input and you can recalculate it yourself.

Step	Value	Where it comes from
Dose	20 g	What a 120 ml phin holds
Caffeine in roasted robusta	2.0–2.7% of weight	The published range for roasted C. canephora is 1.7–4.0%, and one study’s measured mean for green robusta was 2.9%. The band here sits inside both and below the top of the published range
Caffeine present in the dose	400–540 mg	20 g × the above
Extraction into the cup	INFERRED 80–90%	A 2024 filter-brew study recovered 134–165 mg from a 10 g arabica dose, roughly 70–90% of the caffeine that 10 g of arabica holds. A phin has longer contact, and some of the brewed liquid stays in the wet grounds and never reaches the glass
Caffeine in the cup	ESTIMATE: 320–490 mg

Extraction is the input still doing guesswork. At 60% the estimate falls to 240–325 mg; at 100% it rises to 400–540 mg. The band stays wide rather than pretending to a precision we do not have.

The other loose input is the bean. Caffeine in roasted C. canephora is published at 1.7–4.0%, and the one roasted-robusta study we read measured Ecuadorian lots between 0.4% and 2.2% — well below that range. A specific bag can sit outside the band used here in either direction.

For comparison

Every figure in this table was measured. The spread inside each row is as informative as the number.

Drink	Measured caffeine	Basis
A teaspoon of ground coffee in a 160 ml mug	23 mg on average	65 samples, prepared in a laboratory
Instant coffee, a teaspoon in 160 ml	64 mg on average	26 samples
Filter coffee, 10 g dose at 15:1	134–165 mg	Across five roast levels
Brewed coffee, 355 ml (12 fl oz)	113–247 mg	The FDA’s stated range
Espresso as cafés serve it, 23–70 ml	51–322 mg, median 140 mg	20 servings bought from 20 outlets
Phin of Vietnamese robusta, 20 g	ESTIMATE 320–490 mg	Calculated above, not measured

A single espresso is widely quoted at 60–80 mg. When twenty of them were bought and analysed, the range was 51 to 322 mg, a six-fold spread. What sets a drink’s caffeine is how much coffee went into it, which is not something the name on the menu tells you.

Why it is so much higher

The species and the ratio multiply.

The species. One study measuring green beans found robusta at 2.9% caffeine by dry weight against arabica’s 1.8%, and the published ranges for roasted coffee put C. canephora at nearly double C. arabica. Caffeine is part of the plant’s chemical defence against insects, which is the same reason robusta needs less spraying in the field.

The ratio. A phin is dosed at about 1:5. A pour-over is dosed at about 1:16. That is three times more coffee per serving before the species is counted at all.

Roughly 97% of Vietnam’s crop is robusta, so a phin of robusta is what ordinary coffee means in Vietnam. Why that makes the drink taste the way it does, rather than what it does to the milligram count, is covered on Vietnamese coffee.

Caffeine in a cà phê sữa đá

A cà phê sữa đá is a 20 g phin poured over condensed milk and ice, so its caffeine is the phin’s caffeine: ESTIMATE 320–490 mg. The milk changes the sweetness and the body, and it is where effectively all of the drink’s calories sit. The ice only adds water, and the caffeine that dripped out of the phin is all still in the glass.

A tall glass of cà phê sữa đá looks like a long, diluted drink beside a small black cup brewed from the same phin, and the two carry the same caffeine.

The drinks that differ are the ones that change the dose. A bạc xỉu is built milk-first on roughly 12 g, which is where the 190–290 mg row applies. Cà phê đen đá, black and iced, is usually brewed from the same 20 g as the milk version and carries the same caffeine as it.

What changes it

If you	Caffeine
Use arabica instead of robusta	Roughly halves
Drop to a 12 g dose	Falls by about 40%
Add more water at the same dose	Barely changes; you are diluting, not removing
Add ice	No change. The ice adds volume, not dilution of the total
Roast darker	Marginal increase per gram, from mass loss
Measure by scoop rather than by weight	Unpredictable, and the largest real-world variable

Daily intake

This is not medical advice, and we have not measured anything.

The FDA cites 400 mg a day for most healthy adults as an amount not generally associated with negative effects. EFSA’s consultation draft on caffeine put single doses up to 200 mg as raising no safety concern for the general adult population. On the estimate above, one 20 g phin can reach either figure by itself.

Someone used to two mugs of filter coffee a day who switches to two phins of robusta has roughly tripled their caffeine intake, while the habit itself looks unchanged.