Most regular brewed green tea has about 20–45 mg of caffeine per 8 oz (240 ml) cup, with many sources landing around 25–35 mg on average. That’s much less than coffee, which is usually around 80–100 mg per 8 oz.

Quick Scoop: Key Numbers

  • Typical green tea (8 oz): about 20–45 mg caffeine.
  • Common “average”: often cited around 30–35 mg per cup.
  • Wider possible range: roughly 10–75 mg depending on type and brewing, with some matcha going higher.
  • Matcha (powdered green tea): often around 60–70 mg per 8 oz equivalent serving, since you consume the whole leaf.
  • Coffee comparison: brewed coffee usually 80–110 mg per 8 oz, so roughly 2–3× a typical green tea.

Why the Caffeine Number Changes

Several factors explain why one cup of green tea might feel stronger than another.

  • Type of green tea
    • Standard bagged or loose-leaf: usually in the 20–45 mg range.
* Matcha and some shaded Japanese greens (like gyokuro): higher, often 50–70 mg per serving or more.
  • Leaf quality and harvest
    • Younger, shade-grown leaves tend to have more caffeine than older, sun-grown leaves.
  • Brew time and water temperature
    • Hotter water and longer steeping pull more caffeine into the cup.
  • Amount of tea used
    • Using more grams of leaf per cup boosts total caffeine even if the tea style is “mild.”

A simple example: a lightly steeped bag of green tea for 1–2 minutes in cooler water may be closer to the low-20s mg, while a strong, long steep with more leaf can push toward the upper end of the range.

Green Tea vs Other Caffeinated Drinks (HTML table)

Here’s an approximate comparison per 8 oz serving:

Beverage Typical caffeine per 8 oz
Green tea (regular brewed) 20–45 mg (often ~30–35 mg)
Matcha green tea ~60–70 mg (can vary)
Black tea ~45–75 mg
Brewed coffee ~80–110 mg
Soft drinks (cola-type) ~23–37 mg
Energy drinks ~72–80 mg or more
Figures above are typical ranges reported by nutrition and tea references, not exact lab values, and individual brands can fall outside these ranges.

How Many Cups Is Safe?

Most healthy adults are generally advised to stay under about 400 mg of caffeine per day from all sources. With green tea, that usually translates to something like:

  • Around 6–10 cups of regular green tea spread throughout the day (not all at once), depending on strength and your sensitivity.
  • Many people feel best in the 2–4 cup range daily, especially if they are somewhat caffeine-sensitive.

If you’re pregnant, have heart rhythm issues, anxiety, trouble sleeping, or are on certain medications, medical guidelines often recommend stricter limits, so checking with a healthcare professional is wise.

Practical Tips to Control Caffeine

To tune your cup’s kick up or down:

  1. Use cooler water (around 70–80°C / 160–175°F) and shorter steeps (1–2 minutes) for less caffeine and a softer taste.
  2. Use hotter water and longer steeps (3+ minutes) if you want a stronger, more stimulating cup.
  3. Choose lower-caffeine styles (many standard senchas, hojicha, or genmaicha) instead of matcha or shaded high-caffeine greens.
  1. If you’re very sensitive, look for decaf green tea, which typically has only a few mg of caffeine left.

In everyday terms: a cup of green tea is usually a gentle, moderate caffeine boost—stronger than most herbal infusions, but significantly milder than a typical coffee.

Information gathered from public forums or data available on the internet and portrayed here.