Coffee Data Lab · the authority engine

When the internet disagrees,
we run the numbers.

Flagship tool

The Caffeine Calculator · know your dose.

Every drink in our database sourced from lab analyses and manufacturer disclosures. Pick a drink, set your cups, see the mg, and how it stacks against the 400 mg guideline.

Open the calculator →

brew methods covered, ratio to water temperature, every number sourced

journal articles published, every claim cited to its source

drinks in the caffeine calculator, each with a sourced range

scores influenced by brands or affiliates. Zero. Ever.

Data stories

Latest data stories.

Data5 Oct 2026 · 12 min read

Coffee and Cortisol: Does It Actually Spike Your Stress Hormone?

A 96-person trial found caffeine raises cortisol after abstinence, but daily drinkers build partial tolerance within days. Here is the real dose picture.

Data4 Oct 2026 · 13 min read

Coffee and Anxiety: What the Evidence Actually Says

A meta-analysis of 546 people found caffeine's anxiety effect is moderate under 400mg and severe above it. Here is the real dose curve, and who is most at risk.

Data30 Sept 2026 · 12 min read

How Much Caffeine Is in Starbucks Nitro Cold Brew? Why There Is No Venti Size

A Grande Starbucks Nitro Cold Brew carries 280mg of caffeine, and Starbucks caps the drink at Grande because a Venti would land near 430mg.

Data29 Sept 2026 · 12 min read

How Much Caffeine Is in Costa Coffee? The UK Chain That Out-Doses Starbucks

Costa's medium cappuccino carries 325mg of caffeine, per an August 2026 Which? test, almost three and a half times Starbucks' 89mg at the same size.

Data28 Sept 2026 · 12 min read

How Much Caffeine Is in Peet's Coffee? The Official Numbers by Roast, Shot, and Size

Peet's own brewed coffee hits 267mg in a 16oz cup, and its blog reports roast level moves caffeine by about one percentage point, from 1.08% to 1.17%.

Data27 Sept 2026 · 12 min read

How Much Caffeine Is in Panera Coffee? The Official Numbers, by Size and Roast

Panera's own March 2026 guide puts a 16oz coffee at 189mg no matter the roast, and ordering iced with no ice nearly doubles the caffeine in the cup.

Exhibit A: how much caffeine is in cold brew? Depends who you ask.

Starbucks Grande, in-store

43 mg

Starbucks bottled RTD

55 mg

High Brew Triple Shot

69 mg

Lab concentrate, max

123 mg

Same drink name, normalised to 100 ml, and the sourced answers still span 3x. Our data pages publish every source, the method behind it, and a reconciled range, so you can check every number yourself.

When the internet disagrees,we run the numbers.