This tea brewing calculator brews by the numbers: pick a tea type and a water volume, and it returns the grams of leaf, the target water temperature and the steep time — the three variables that decide whether the cup tastes like the leaf or like regret.

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The Three Variables of a Decent Cup

Tea brewing fails on exactly three dials — leaf dose, water temperature, steep time — and the standard parameters are published and consistent across serious tea references: about 2.5 g of leaf per 8 oz (a scant teaspoon for most black/green teas, more for voluminous whites), green at 175 °F for 2–3 minutes, black at a full 212 °F boil for 3–5, oolong at 195 °F with re-steeps, white at 170 °F long and gentle, herbals at boiling for 5–7. The defaults brew one 8 oz cup of green tea: 2.5 g, 175 °F, 2–3 minutes. Scale is linear in the leaf (a 32 oz pot of black tea takes 10 g), but temperature and time don’t scale — they stay per-type constants, which is exactly what the calculator encodes: choose type and volume, receive all three numbers.

The chemistry under the dials: temperature controls WHICH compounds extract fastest (bitter catechins and caffeine surge at high temperature; sweet amino acids extract more temperately), time controls HOW MUCH of everything has extracted, and dose controls the concentration ceiling. Bitter green tea is almost always a temperature crime (boiling water), occasionally a time crime; weak tea is a dose crime that longer steeping cannot fix without also turning bitter — raise leaf, not minutes. Tea bags invert the convenience: fannings extract so fast that 2 minutes is plenty and the bag must leave on time. Everything else — agitation, vessel material, water mineral content — is real but second-order; nail the three dials first.

Worked Examples (Verified)

  • Default cup (green, 8 oz): 2.5 g leaf, 175 °F, 2–3 min.
  • Teapot of black (32 oz): 10.0 g leaf, 212 °F, 3–5 min.
  • White tea mug (12 oz): 4.5 g leaf, 170 °F, 4–5 min.

Tea Brewing Discipline

  • Weigh leaf when you can: “1 tsp” of rolled oolong and of fluffy white tea differ by 3× in mass — grams are the honest unit (2.5 g ≈ 1 tsp for CTC black, 2–3 tsp for leaf whites).
  • No thermometer? Boiling water rested 2 minutes ≈ 195 °F, 5 minutes ≈ 175 °F (open kettle, room temperature kitchen) — good enough for oolong and green respectively.
  • Decant fully at time: the second cup from leaves left in water is a different, worse beverage (a basket infuser or a second pot solves it structurally).
  • Re-steep the good stuff: quality oolong, green and pu-erh leaves give 3–5 infusions; spent-at-once is a black-tea habit.
  • Water matters quietly: heavily chlorinated or very hard water flattens tea; fresh, filtered, once-boiled water is the standard advice because it is correct.

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Frequently Asked Questions

How much tea leaf per cup?

About 2.5 g per 8 oz of water for black and green teas — roughly one teaspoon of typical leaf — rising to ~3 g for oolong and white teas whose volume-to-mass is airier. The calculator scales leaf linearly with your volume and tea type: a 32 oz pot of black tea takes 10 g. When in doubt, weigh once to calibrate your spoon for that specific tea, then spoon forever.

What temperature for green tea?

About 175 °F (80 °C), steeped 2–3 minutes. Boiling water is the single most common green-tea error: it accelerates catechin extraction into bitterness and cooks the delicate aromatics. Japanese greens (sencha, gyokuro) run cooler still (140–170 °F). If your green tea has always tasted harsh, temperature — not the tea — is the first suspect; this page’s per-type temperatures exist to acquit the leaf.

How long should tea steep?

By type: green 2–3 minutes, black 3–5, oolong ~3 (with re-steeps), white 4–5, herbal 5–7. Past the window, extraction doesn’t stop — tannins keep accumulating and the cup turns astringent, while caffeine extraction also climbs. Under-steeping is correctable (put it back, briefly); over-steeping is not (dilute with hot water and learn the timer religion). The calculator prints the range per type with the leaf dose and temperature together.

Can I re-steep tea leaves?

Yes for whole-leaf oolong, green, white and pu-erh — 3 to 5 infusions is normal, each slightly longer, and connoisseurs often prize the second and third steeps most. Rinse the leaves with a splash of hot water first for compressed pu-erh. Black tea and bagged fannings extract nearly completely on the first steep and give a thin second cup. Herbal blends vary: roots and spices re-steep reasonably, delicate flowers don’t.

What’s the difference between Western and gongfu brewing?

Ratios and repetitions: Western (this calculator’s default) uses ~2.5–3 g per 240 mL with 2–5 minute steeps, one or two infusions. Gongfu uses 5–7 g per 100 mL with many 15–45 second steeps, tasting the leaf’s evolution across 6–10 cups. Neither is wrong; they’re different instruments. Gongfu numbers don’t scale from Western ones by any simple factor — if you brew gongfu, the leaf-per-100-mL figure on your tea’s vendor page is the guide.

Does tea have much caffeine?

An 8 oz cup typically lands 30–50 mg (black at the high end, green lower, white variable) against coffee’s ~95 mg — but the dials on this page move it: hotter water and longer steeps extract more caffeine, and leaf dose matters most. Herbal tisanes (including rooibos) are naturally caffeine-free. The calming-with-alertness feel of tea is caffeine moderated by L-theanine, which extracts readily even at green-tea temperatures.

Why did my tea turn bitter?

Almost always one of three dials: water too hot for the type (boiling on green — the classic), steep too long, or too much leaf for a CTC/bagged grade whose small particles extract violently fast. Diagnose in that order. The fix for a pot already bitter is dilution with plain hot water, never more steeping of anything, and the fix for next time is printed in this calculator’s three numbers.

Is this tea brewing calculator free?

Yes — free, instant, no sign-up. Choose a tea type and water volume for leaf grams, water temperature and steep time.