An 8 oz cup of green tea usually has about 30–50 mg of caffeine, while an 8 oz cup of brewed coffee averages around 90–100 mg, often ranging roughly 80–200 mg depending on type and preparation. So, cup for cup, coffee typically has about 2–3 times more caffeine than standard green tea.

How Much Caffeine in Green Tea vs Coffee?

Quick Scoop

  • Green tea: about 30–50 mg caffeine per 8 oz cup on average.
  • Typical brewed coffee: about 90–100 mg per 8 oz, with a broader range of roughly 80–200 mg.
  • Result: Coffee usually has 2–3× more caffeine per cup than regular green tea.
  • Matcha (powdered green tea) is an exception: ~60–70 mg per 8 oz, closer to a mild coffee.

Standard Caffeine Numbers

Below is an approximate comparison for a single 8 oz (about 240 ml) serving.

html

<table>
  <thead>
    <tr>
      <th>Beverage</th>
      <th>Typical caffeine per 8 oz</th>
      <th>Notes</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>Green tea (regular brewed)</td>
      <td>≈ 30–50 mg[web:3]</td>
      <td>Many sources report ~25–40 mg; averages vary by brand and brew time.[web:1][web:3][web:9]</td>
    </tr>
    <tr>
      <td>Matcha green tea</td>
      <td>≈ 60–70 mg[web:1]</td>
      <td>Ground leaf powder is consumed fully, so caffeine is higher than standard green tea.[web:1]</td>
    </tr>
    <tr>
      <td>Coffee (brewed, drip)</td>
      <td>≈ 90–100 mg[web:3][web:5]</td>
      <td>Common range roughly 80–200 mg depending on beans, roast, and brew strength.[web:3]</td>
    </tr>
    <tr>
      <td>Instant coffee</td>
      <td>≈ 27–173 mg[web:3]</td>
      <td>Very variable; many instant coffees sit a bit below typical brewed coffee.[web:3]</td>
    </tr>
    <tr>
      <td>Espresso (per 8 oz equivalent)</td>
      <td>≈ 240–720 mg[web:3]</td>
      <td>Espresso is usually drunk in 1–2 oz shots; per ounce it is far more concentrated.[web:3]</td>
    </tr>
  </tbody>
</table>

Why the Numbers Vary

Several factors change how much caffeine you actually get in your cup.

  • Type of tea or coffee
    • Some green teas are naturally lighter; powdered green teas like matcha are stronger.
* Different coffee beans and blends naturally carry different caffeine levels.
  • Brewing method and time
    • Longer steeping or hotter water usually pulls more caffeine from tea leaves.
* Coffee brewed stronger (more grounds per water) or with certain methods (like espresso) has more caffeine per ounce.
  • Serving size
    • Café servings often exceed 8 oz, so total caffeine can be much higher than “per cup” estimates.
* A large coffee (12–16 oz) can easily push you toward or above 200 mg in a single drink.

How They Feel Different

Even when the numerical caffeine dose overlaps, many people notice that coffee and green tea feel different in the body.

  • Green tea
    • Often described as a gentler, smoother lift.
    • Contains L-theanine, an amino acid that can promote a calmer, more focused state and may blunt some of caffeine’s jittery edge.
  • Coffee
    • Tends to hit faster and harder for most people, especially on an empty stomach.
    • More likely to cause jitters or a “crash,” particularly at higher doses or in sensitive drinkers.

A practical example: one 8 oz coffee (~100 mg) can feel like multiple cups of green tea (~30–50 mg each), even if the total daily caffeine ends up similar.

What This Means for Your Day

  • If you want maximum alertness quickly, coffee usually delivers more caffeine in a single cup.
  • If you prefer gentler, more sustained focus with less risk of jitters, several cups of green tea spread through the day might suit you better.
  • Matcha sits in between : closer to a lighter coffee in caffeine, but with tea’s L-theanine profile.

For most healthy adults, a commonly cited upper limit is about 400 mg of caffeine per day from all sources, which might be around 4 small coffees or 8–10 cups of green tea, though individual tolerance varies.

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