Nutritionally these two are almost nothing, and that is the honest answer. Brewed black coffee and brewed green tea are both about 1 calorie per 100 ml, with no meaningful fat, protein, carbohydrate or fibre. Coffee carries a little more potassium (49 mg against 8 mg) and that is the extent of what a nutrition table can tell you.
The real differences are in compounds the table does not cover: coffee has roughly two to three times the caffeine of green tea cup for cup, and each carries a different family of polyphenols — chlorogenic acids in coffee, catechins in green tea.

| Nutrient | Coffee | Green Tea |
|---|---|---|
| Calories | 1 kcal | 1 kcal |
| Protein | 0.12 g | 0.22 g ✓ |
| Total Carbohydrate | 0 g | 0 g |
| Dietary Fiber | 0 g | 0 g |
| Total Sugars | 0 g | 0 g |
| Total Fat | 0.02 g | 0 g |
| Saturated Fat | 0 g | 0 g |
| Sodium | 2 mg | 1 mg ✓ |
Notable compounds in each
When to choose each
Reach for coffee when you want the stronger stimulant effect, and for chlorogenic acid — coffee is most people’s largest dietary source of it. Reach for green tea for a gentler lift, and for catechins including EGCG. Green tea also contains theanine, which is often credited with why its caffeine feels less abrupt.
Coffee vs green tea: what the nutrition panel does not show
Both figures are for the plain brewed drink with nothing added. Milk, sugar and syrups change the picture entirely — they are what turn a 1-calorie drink into a 200-calorie one, and they are the single biggest variable in either.
Caffeine content varies enormously within each: brewing time, leaf or bean quantity and grind all move it more than the choice between coffee and tea does at the margins. A strong green tea can out-caffeinate a weak coffee.
Common questions
Is green tea healthier than coffee? Neither has a clear edge. Both are associated with favourable outcomes in large observational studies, and both carry different polyphenols. What you add to them affects your diet far more than which one you choose.
How much caffeine is in green tea vs coffee? A cup of brewed coffee typically has two to three times the caffeine of a cup of green tea, though both vary widely with strength and brewing time. Green tea also contains theanine, which many people find takes the edge off.
Does green tea burn fat? The effect is real but small. Catechins and caffeine together produce a modest increase in energy expenditure in trials; it is not large enough to drive weight loss on its own, and green tea drunk plain is mainly useful as a zero-calorie replacement for something else.
Can you drink coffee and green tea on the same day? Yes. The main thing to watch is total caffeine rather than the source — most guidance puts around 400 mg a day as a reasonable ceiling for healthy adults, which is roughly four cups of coffee. Both also contain compounds that reduce iron absorption, so drinking them away from meals helps if your iron is low.