Tea Steeping Time & Temperature Calculator

Tea Brewing Guide

What do I need to know about Temperature is Critical?

Water temperature is the single biggest variable in tea quality — especially for green tea. Boiling water (100°C) on a delicate green tea extracts bitter catechins and tannins, completely destroying the flavour. Temperature guide: black tea (full oxidised): 95-100°C. Darjeeling first flush: 85-90°C. Oolong (light): 80-90°C. Oolong (dark): 90-95°C. Green tea (standard): 75-80°C. Green tea (delicate, shade-grown): 60-70°C. White tea: 75-85°C. Herbal infusions: 95-100°C, since these are not true tea and contain no tannins to over-extract, meaning boiling water and longer steeping cause no bitterness.

What's the key thing to understand about The Chemistry of Bitterness?

Tea flavour compounds are extracted at different rates: Amino acids (L-theanine) — sweet, umami, calming — extract quickly at low temperatures. Catechins (EGCG) and other polyphenols — astringent, bitter — extract slowly at low temperatures but very rapidly at high temperatures. Caffeine — energising, slightly bitter — extracts moderately across temperatures. The ideal brew extracts maximum amino acids and moderate catechins. High temperature and long steeping time extract too many catechins, resulting in the bitter, astringent taste associated with over-brewed tea.

What should I know about Multiple Infusions (Gongfu Style)?

High-quality whole-leaf teas can be steeped multiple times — each infusion reveals different flavour profiles. First infusion: often slightly muted as leaves begin to open. Second and third: typically the best, as leaves fully expand and optimal flavour extraction occurs. Fourth, fifth, sixth: gradually lighter but still pleasant. Chinese gongfu brewing: uses a high ratio of leaves to water (5-8g per 100-120mL), very short steeping times (15-30 seconds for the first infusion), increasing by 5-10 with each subsequent infusion as the leaves gradually release less flavour.

What should I know about Water Quality?

Water quality significantly affects tea flavour. Hard water (high calcium and magnesium): reacts with tea tannins and polyphenols, creating a grey film on the surface, dulling flavour, and increasing astringency. Best water for tea: filtered water (reduces chlorine and minerals) or soft water. Ideal TDS (total dissolved solids) for tea: 50-150 mg/L. Very soft or distilled water: tastes flat — needs a small amount of minerals for body. UK water hardness varies enormously: London, for example, has very hard water, at around 300 parts per million, which can noticeably affect tea flavour compared to using filtered or soft water.

What should I know about Why Water Temperature Varies by Tea Type?

The tea_temp_c this calculator recommends differs substantially by tea_type because different teas are processed differently and contain different balances of flavor and bitterness compounds that respond differently to heat. Green and white teas are the least oxidized and contain delicate catechins and amino acids that can turn harsh, grassy, or bitter if steeped in fully boiling water, which is why they're typically recommended at a notably lower temperature, often in the 70–85°C range depending on the specific tea. Black tea and most herbal infusions are more robust and generally need water close to or at a full boil (95–100°C) to properly extract their flavor compounds in a reasonable steeping time. Oolong sits in between and varies with its specific oxidation level, which can range from close to green tea's lightness to much closer to black tea's fuller oxidation. Using boiling water on a delicate green tea, or under-heated water on a robust black tea, is one of the most common reasons a cup of tea tastes "wrong" even when the steep time itself was correct.

What should I know about Why Later Infusions Need Longer Steeps?

When the same tea leaves are steeped multiple times — common with higher quality whole-leaf teas, and reflected in this calculator's tea_second_infusion output — the most easily soluble flavor and aroma compounds come out fastest in the first infusion, leaving progressively less readily available flavor in the leaves for each subsequent steep. To compensate and keep later cups tasting comparably full rather than progressively weaker and more watery, the common practice is to increase the steeping time somewhat for the second and third infusions (and sometimes raise the temperature slightly too, for teas that can tolerate it) rather than keeping every infusion at the same duration. This is especially noticeable and deliberately exploited with gongfu-style brewing, where a relatively small amount of leaf is steeped very briefly but many times in succession, with each infusion's time nudged upward to draw out the leaves' full flavor potential across the session rather than extracting everything (and over-extracting the bitterness) in one long first steep.

What do I need to know about Loose Leaf vs Tea Bag Steeping Differences?

Loose leaf tea and tea bags often need different steeping approaches even for the same tea type, mainly because of leaf size and surface area. Tea bags typically contain finely cut or broken leaf (sometimes called 'fannings' or 'dust' in the tea trade), which has much greater surface area relative to its volume than whole or large-leaf loose tea, meaning it extracts flavour and caffeine faster — this is why tea bags are generally steeped for a shorter time (often 2-4 minutes for black tea) than the equivalent loose leaf version (often 3-5 minutes), despite being nominally the 'same' tea. Using a loose-leaf steeping time for a tea bag risks over-extraction and excessive bitterness, since the bag's finer particles release tannins and bitter compounds faster than whole leaves would in the same time. Loose leaf tea also benefits more from having room to expand and unfurl during steeping, which is why a spacious infuser or simply steeping loose in the pot (then straining) often gives a better result than a tightly packed infuser ball that restricts the leaves' movement and water circulation. When following a steeping guide, always check whether it was written with loose leaf or bagged tea in mind, since applying one to the other by habit is a common reason a cup tastes stronger or weaker than expected.

What's a Consolidated Steep Temperature and Time Reference by Tea Type?

Pulling the temperature and first-infusion time guidance together into one lookup table makes it faster to get a new tea right the first time, without needing to cross-reference multiple separate rules about oxidation level and leaf size.

This table is a starting point rather than a fixed rule — leaf size, how tightly it's rolled, and personal taste all shift the ideal time within these ranges, which is exactly why tasting and adjusting on the second cup (shorter if too bitter, longer if too weak) remains the most reliable calibration method for any specific tea.

Does Tea Leaf Size Change the Steep Time at the Same Temperature?

Leaf form has a meaningful effect on how fast the same tea infuses, independent of tea type. Finely cut or broken leaves — as used in most standard tea bags — expose far more surface area to the water than whole or large-leaf loose tea, so bagged tea typically needs only 2-4 minutes to reach full strength at a given temperature, while the same tea as whole-leaf loose tea often needs several minutes longer to extract comparably, since the water has to penetrate deeper into intact, rolled leaves rather than acting on already-fragmented particles. This is also why steeping a tea bag for the time recommended for loose leaf of the same type routinely produces an over-extracted, bitter cup — the fine particles release their compounds much faster, so matching loose-leaf steep times to a tea bag effectively doubles the extraction relative to what the leaf form needs.

Worked Example: Timing a Second Gongfu Infusion

Gongfu-style brewing uses a high leaf-to-water ratio with short, repeated infusions rather than one long steep. Suppose a first infusion of oolong at 95C steeps for 20 seconds. For the second infusion, the standard adjustment is adding roughly 5-10 seconds to account for the leaves having opened less fully than they will by the third or fourth infusion. That gives a second infusion time of about 25-30 seconds at the same 95C water temperature. By the fourth or fifth infusion, as the leaves fully unfurl and release flavour more slowly, steep times typically stretch to 45-60 seconds to extract a comparable strength cup, and a well-made oolong can often sustain 6-8 enjoyable infusions this way before flavour meaningfully fades. The general pattern across most gongfu-brewed teas is: start short, add roughly 5-10 seconds per subsequent infusion for the first few rounds, then add larger increments as the leaf's capacity for a strong early extraction diminishes.