Black Tea vs Green Tea: Which Has More Caffeine? A Complete Guide

Black tea or green tea: which one contains more caffeine?

It's an interesting question, especially if you enjoy a cup of black tea with breakfast and green tea throughout the day. Both are familiar drinks, yet their caffeine content can be surprisingly different.

According to reference values published by Japan's Ministry of Agriculture, Forestry and Fisheries, brewed black tea contains approximately 30mg of caffeine per 100ml, while sencha green tea contains around 20mg. Under these standard brewing conditions, black tea contains about 1.5 times as much caffeine as sencha.

However, there's an interesting twist. Gyokuro, a premium Japanese green tea, has a reference caffeine concentration of approximately 160mg per 100ml. Matcha, hojicha and genmaicha also have their own characteristics.

So the answer depends on which tea you're comparing, how it's prepared and how much you drink.

In this guide, we'll compare black tea and different types of green tea, explore what makes their caffeine levels vary and discover how brewing methods influence your cup.

Along the way, we'll share a few fascinating facts about tea culture, from the meaning of Orange Pekoe to the way tea leaves move inside a teapot. Whether you're a dedicated tea lover or simply curious about caffeine, there's plenty to discover.

1. Black Tea vs Green Tea: Which Has More Caffeine?

The easiest way to compare black and green tea is to look at their caffeine content using the same volume.

But there's one detail worth remembering: green tea isn't just one drink.

Sencha, gyokuro, hojicha and genmaicha are all familiar styles of Japanese tea, yet their ingredients, production methods and brewing traditions are different.

Let's begin by comparing typical caffeine concentrations in five popular teas.

The first surprise is that ordinary black tea has a higher reference caffeine concentration than sencha, one of Japan's most popular green teas.

The second surprise is gyokuro. Its reference concentration is considerably higher than either black tea or sencha.

Before comparing them too literally, however, it's important to understand what these figures represent.

The table shows caffeine concentration per 100ml, rather than the amount in every cup you might prepare at home.

For example, using the reference concentration for black tea, a 200ml serving would contain approximately 60mg of caffeine. A 200ml serving of sencha at its reference concentration would contain approximately 40mg.

These are calculated examples, not universal measurements for every cup.

Gyokuro is particularly interesting because it is traditionally prepared using a relatively small amount of water and enjoyed in small servings. A high concentration per 100ml therefore needs to be considered alongside the actual amount served.

Matcha deserves a separate explanation because it is made by whisking powdered tea directly into water rather than steeping leaves and removing them.

Japan's Ministry of Agriculture, Forestry and Fisheries provides an example in which 1.5g of matcha powder contains approximately 48mg of caffeine when prepared with 70ml of water.

This illustrates why the amount of matcha powder matters when estimating caffeine intake.

The main takeaway is simple: black tea generally has more caffeine than sencha under these reference conditions, but the wider world of Japanese tea offers considerable variety.

And once you start exploring that variety, you'll discover that the appeal of tea goes far beyond caffeine numbers.

2. Why Do Black and Green Tea Have Different Caffeine Levels?

If black tea and green tea contain different amounts of caffeine, does that mean they're made from completely different plants?

Surprisingly, both are generally produced from the same species: Camellia sinensis, the tea plant.

The differences between these teas begin with the leaves themselves and continue through the way they're processed.

Black tea undergoes extensive enzymatic oxidation, which contributes to its darker appearance and distinctive aromas. Green tea is heated earlier in processing to limit oxidation, helping preserve its fresh colour and flavour.

The tea plant naturally contains caffeine, however, and oxidation alone does not determine the amount that ultimately appears in your cup.

Factors such as the tea plant variety, growing conditions, harvesting season and the parts of the plant used can all contribute to differences in the composition of tea leaves.

Young buds and mature leaves, for example, may contain different proportions of naturally occurring compounds.

Another important distinction is the difference between caffeine contained in dry tea leaves and caffeine extracted into water.

When you brew loose-leaf tea, you're creating an infusion. Some compounds in the leaves move into the hot water, while others remain in the leaves.

The amount extracted depends partly on the quantity of tea, water volume and brewing conditions.

This helps explain an important detail in the Japanese food composition tables: the reference values for black tea and sencha are based on different preparation methods.

Notice that the quantity of leaves, water volume and steeping time are different.

These measurements are useful reference values, but they do not represent an experiment in which every tea was brewed in exactly the same way.

If the same teas were prepared using different conditions, their measured caffeine concentrations might also differ.

This is one reason published comparisons can sometimes appear inconsistent. Different studies may use different teas, quantities, temperatures or brewing times.

Understanding the method behind a number makes it much easier to interpret what you're reading.

It also highlights something wonderful about tea. The final drink is shaped not only by where a tea plant grows, but also by the traditions and techniques used to prepare its leaves.

Whether you're exploring an aromatic Assam or a delicate Japanese sencha, the ingredients and preparation are part of what makes every cup distinctive.

3. Gyokuro, Matcha, Hojicha and Genmaicha: Exploring Japanese Tea

Once you discover how much variety exists within green tea, it's easy to see why Japanese tea has such a rich culture.

Sencha, gyokuro, matcha, hojicha and genmaicha all have their own personalities, from vibrant green flavours to warm, roasted aromas.

Let's look beyond the caffeine comparison and discover what makes each style special.

Gyokuro: A distinctive tea known for its rich umami flavour.

Gyokuro is one of Japan's premium green teas. The tea plants are shaded before harvesting, a cultivation technique that contributes to the distinctive character of the leaves.

The resulting tea is prized for its deep umami, elegant fragrance and carefully balanced flavour.

Gyokuro is often prepared with relatively small quantities of water, giving it a different drinking style from a large cup of everyday green tea.

The Japanese food composition tables, for example, specify 10g of gyokuro leaves brewed in 60ml of water at 60°C for 2.5 minutes.

This is a particularly concentrated preparation. It's useful to remember that caffeine concentration and the total amount consumed are two separate considerations.

Matcha: Enjoying finely powdered tea leaves.

Matcha is made from specially prepared tea leaves ground into a fine powder.

Unlike ordinary loose-leaf green tea, where the leaves are removed after brewing, matcha is whisked directly into water, and the finely powdered tea becomes part of the drink.

Matcha is closely associated with the Japanese tea ceremony, but it's also enjoyed in contemporary drinks such as matcha lattes and used in cakes and desserts.

Because the powdered leaves are consumed, the amount of matcha used is an important consideration when comparing caffeine content.

Hojicha: Warm, roasted aromas.

Hojicha is made by roasting tea leaves, producing its recognisable toasted aroma and warm brown appearance.

Its distinctive flavour has inspired everything from traditional hot tea to hojicha lattes and desserts.

The caffeine content depends on the leaves and preparation used, so the roasted flavour alone isn't a reliable measurement of caffeine.

Genmaicha: Green tea meets roasted rice.

Genmaicha is a Japanese tea traditionally made by combining green tea leaves with roasted rice.

The rice contributes a wonderfully nutty, toasted character that complements the freshness of the tea.

It's a lovely example of how combining familiar ingredients can create an entirely different tea-drinking experience.

And of course, the world of black tea is just as varied.

Assam teas from India are often celebrated for their rich, malty character, while Darjeeling teas can offer delicate and highly distinctive aromas.

Sri Lankan black teas, commonly known as Ceylon teas, also have an impressive range of styles shaped by growing regions and processing traditions.

Learning about these differences gives you more ways to choose tea, whether you're interested in its origins, its aroma or how it complements your favourite foods.

4. Does Brewing Temperature or Steeping Time Change Caffeine Levels?

Have you ever brewed your favourite black tea and noticed that it tastes a little stronger than the last time?

Even with exactly the same tea leaves, differences in water temperature and steeping time can influence the flavour and aroma of the finished drink.

Those brewing conditions can also influence the amount of caffeine extracted into the water.

A 2025 study published in the scientific journal Foods investigated caffeine and L-theanine levels in six types of tea, including black, green and oolong tea.

The researchers examined how different brewing temperatures and steeping times influenced the compounds measured in the prepared infusions.

Their results showed that longer brewing times generally increased the amount of caffeine extracted under the conditions studied.

However, the extent of the change varied between teas and brewing conditions.

The relationship with water temperature was more nuanced. In the study's comparisons, a statistically significant temperature-related change in caffeine content was observed for oolong tea, rather than consistently across every tea type.

This means there is no single temperature adjustment that will reduce caffeine by a fixed percentage in every tea.

For tea lovers, it's useful to consider the overall brewing method rather than relying on temperature or time alone.

So how should you prepare your favourite tea?

A good starting point is the brewing guidance provided with the product.

Many black teas are prepared with freshly boiled water and steeped for a few minutes, allowing their distinctive fragrance and body to develop.

A full-bodied Assam can be particularly enjoyable with milk, while the delicate aroma of certain Darjeeling teas may be lovely when enjoyed without additions.

Japanese green teas offer different traditions. Sencha is often prepared with water that has cooled slightly after boiling, while gyokuro is commonly enjoyed using cooler water and a more concentrated infusion.

Different teas invite different preparation styles, and exploring these traditions can become an enjoyable part of your tea routine.

If you're looking to reduce caffeine intake, adjusting the serving size or choosing a naturally caffeine-free rooibos blend may be more straightforward than trying to control caffeine through steeping time alone.

You might enjoy a fragrant black tea with breakfast, explore a favourite green tea during the day and choose vanilla rooibos for an evening tea break.

With so many flavours and preparation styles available, tea offers plenty of ways to create a routine that suits your preferences.

5. How Much Caffeine Is in a Cup of Tea? Cups, Mugs and Bottled Drinks

A cup of black tea with breakfast. Another while taking a break from work. Perhaps a third when you settle down with a book in the afternoon.

If tea is part of your daily routine, you may have wondered how much caffeine you're actually drinking.

One of the simplest ways to understand your intake is to look at the size of your cup.

A delicate teacup might hold 150ml, while a generous mug could hold 300ml or more. Even when the tea is brewed to exactly the same strength, those two servings contain different total amounts of caffeine.

As we explored in Chapter 1, Japan's Ministry of Agriculture, Forestry and Fisheries gives a reference value of approximately 30mg of caffeine per 100ml for brewed black tea.

Using that figure, we can estimate how the caffeine content changes with the amount you drink.

Here's a useful example: two 150ml cups of black tea would contain approximately 90mg of caffeine in total, based on these reference values.

That is the same calculated amount as one 300ml mug of tea brewed to the same concentration.

So, when someone says they drink three cups of tea a day, it's worth remembering that the actual volume can vary considerably.

You might even enjoy measuring your favourite mug with a kitchen measuring jug. It's a surprisingly simple way to learn more about your everyday tea routine.

Bottled tea brings another detail into the picture.

Some ready-to-drink teas provide caffeine information per 100ml, while others may list the amount per bottle or serving. Checking which measurement is being used makes comparisons more meaningful.

Commercial bottled tea and homemade tea may contain different concentrations because the ingredients and production methods are different. Where available, the product's own caffeine information is the most useful reference.

But how many cups of tea should you drink each day?

There isn't one universal number that suits everyone. Caffeine sensitivity varies, and factors such as age, pregnancy, breastfeeding and individual health circumstances can influence appropriate intake.

Rather than focusing on cup numbers alone, consider the type of tea, serving size and other sources of caffeine in your day.

For example, you might enjoy a fragrant black tea at breakfast and choose naturally caffeine-free rooibos later in the evening.

With a little knowledge about serving sizes, you can make more informed choices while continuing to enjoy the flavours and traditions you love.

6. Milk Tea, Iced Tea and Tea Bags: Does Preparation Change Caffeine Content?

Straight black tea, a creamy milk tea and a refreshing glass of iced tea may all begin with the same tea leaves.

Yet each preparation creates a different drinking experience. The aroma, texture and flavour can change considerably.

So what happens to the caffeine?

Let's begin with milk tea.

Imagine brewing 150ml of black tea and adding 50ml of milk. You now have a 200ml drink with a smoother, creamier flavour.

Adding milk dilutes the caffeine concentration in the finished drink, because the same caffeine is now distributed through a larger volume.

However, the total amount of caffeine that was originally present in the brewed tea remains essentially unchanged simply because milk has been added.

If you prepare a 200ml milk tea using less brewed tea and more milk, the total caffeine amount may be lower because you have used a smaller volume of tea.

That's an important distinction: diluting a tea and using less tea are not quite the same thing.

Iced tea follows a similar principle.

If you brew hot tea and pour it over ice, the melting ice increases the total volume and dilutes the drink. But adding ice does not, by itself, remove the caffeine already extracted from the tea leaves.

Cold-brewed tea is a little different. It is prepared using water at a lower temperature over a longer period, and the final caffeine content depends on the ingredients, leaf quantity and brewing conditions.

For the most enjoyable result, choose a product suitable for your intended preparation method and follow its instructions. Cold-brewed tea should also be prepared and stored hygienically.

Now, what about tea bags and loose-leaf tea?

Tea bags are wonderfully convenient, particularly when you're preparing a quick cup at work or enjoying tea while travelling.

Loose-leaf tea, on the other hand, gives you more control over the quantity of leaves and offers the pleasure of watching them unfurl in a teapot.

Some tea bags contain finely cut leaves, which may release their compounds differently from larger leaves. However, that does not mean every tea bag automatically produces a higher-caffeine drink than every loose-leaf tea.

The tea itself, the amount used, the particle size and the brewing conditions all matter.

A 2025 study published in the journal Foods examined different tea types and brewing methods, including comparisons between tea bags and loose-leaf preparations. It found that the preparation format could influence caffeine measurements under particular conditions.

For everyday tea drinkers, the practical message is straightforward: choosing tea bags or loose leaves is partly a matter of convenience and personal enjoyment, while caffeine content depends on several factors working together.

A tea bag might be perfect for a busy morning. On a quiet weekend, you might prefer to measure out loose leaves, warm your favourite teapot and enjoy the whole brewing ritual.

Both approaches offer their own pleasures, and neither has to replace the other.

7. Black Tea or Green Tea: How to Choose by Flavour, Food and Occasion

Caffeine content is useful to understand, but there's another delightful reason to explore different teas: their flavours.

Black tea and green tea have distinct personalities, and the foods you enjoy can make those differences even more interesting.

Imagine a breakfast of warm toast, buttery croissants or freshly baked scones.

A rich black tea can be a lovely match. Assam, for example, is appreciated for its full-bodied, often malty character, which also makes it a popular choice for milk tea.

The depth of black tea can complement the richness of butter, milk and baked goods, creating a familiar and satisfying breakfast combination.

Green tea offers a different experience.

A cup of sencha, with its fresh and gently astringent flavour, can pair beautifully with Japanese sweets or a traditional Japanese meal.

Try it with a small sweet made from red beans or rice. The contrast between the tea's character and the sweetness of the food can be particularly enjoyable.

For black tea lovers who enjoy a more fragrant experience, flavoured teas open up even more possibilities.

One of the best-known examples is Earl Grey, traditionally associated with the bright citrus aroma of bergamot.

Some Earl Grey blends highlight fresh citrus notes, while others combine bergamot with flowers, vanilla or caramel-inspired aromas.

This means two teas carrying the Earl Grey name may create quite different impressions in the cup.

A classic citrus-forward Earl Grey can be an appealing choice when you want a lively, aromatic black tea. A cream-style Earl Grey may be especially enjoyable with milk and sweet pastries.

You can also create a small tea collection for different occasions.

Perhaps a bright Earl Grey for breakfast, a delicate green tea with lunch and a vanilla-scented rooibos infusion in the evening.

Rooibos is made from a South African plant rather than the traditional tea plant, making it a naturally caffeine-free alternative when you want to enjoy another style of tea.

There is no need to choose one favourite forever. Exploring a few different styles allows you to enjoy tea according to the season, the meal or simply your mood.

When deciding what to brew next, ask yourself three simple questions: What am I eating? Which aromas appeal to me? And what kind of tea experience would I enjoy right now?

The answers may lead you to a familiar favourite or introduce you to a blend you've never considered before.

8. Discover Tea Total: New Zealand Earl Grey and Rooibos Tea

Once you begin exploring the differences between black and green tea, you may feel inspired to discover a few new favourites.

At Brilliant Life Products NZ, we offer a selection of teas from Tea Total, a New Zealand tea brand known for its varied range of traditional black teas, flavoured blends, herbal infusions and rooibos teas.

One of the most enjoyable parts of exploring Tea Total is discovering how familiar black tea can take on an entirely different character when paired with fragrant citrus, flowers, vanilla or other carefully selected ingredients.

Here are three distinctive teas from our collection to consider for your next tea break.

For lovers of bright citrus aromas: Earl Grey Special Tea.

Tea Total's Earl Grey Special combines black tea and bergamot with a fragrant selection of botanicals, including cornflower, lemon peel, lemongrass, marigold, jasmine and safflower.

The refreshing citrus character of bergamot is complemented by the lively notes of lemon peel and lemongrass, creating an aromatic black tea with a distinctive personality.

Its balanced character makes it enjoyable as a straight black tea, while the tea's body also works well with a little milk.

It's a lovely choice for breakfast, an afternoon tea break or any occasion when you feel like a fragrant cup with a refreshing citrus twist.

If you already enjoy classic Earl Grey, this blend offers a chance to discover a more layered combination of citrus and floral aromas.

Explore Tea Total Earl Grey Special

For vanilla and caramel lovers: Earl Grey Cream Tea.

This Tea Total blend brings together black tea, bergamot, vanilla and caramel for a wonderfully fragrant twist on traditional Earl Grey.

The familiar citrus aroma of bergamot meets soft, sweet-smelling vanilla and caramel notes, creating a smooth and inviting tea experience.

It can be enjoyed without additions, but is particularly appealing with milk, which complements the blend's creamy, dessert-inspired character.

Imagine a warm cup alongside a freshly baked scone, buttery biscuit or slice of cake. The combination feels perfectly suited to a leisurely afternoon tea.

For anyone who enjoys milk tea or flavoured black teas, Earl Grey Cream is a delightful option to explore.

Explore Tea Total Earl Grey Cream

For a naturally caffeine-free alternative: Madagascar Vanilla Rooibos Tea.

Rooibos comes from a plant different from traditional black or green tea, and is naturally free from caffeine.

Tea Total's Madagascar Vanilla Rooibos combines rooibos and vanilla, offering a mellow tea with a gentle, sweet-smelling aroma.

The smooth character of rooibos and the soft fragrance of vanilla create a welcoming cup that is particularly enjoyable with biscuits or baked desserts.

It also provides another option for occasions when you prefer a drink made from naturally caffeine-free ingredients.

For example, you could enjoy your favourite black tea in the morning and prepare vanilla rooibos in the evening while reading a book or spending time with family.

If you've never explored flavoured rooibos before, its distinctive character may be a pleasant discovery.

Explore Tea Total Madagascar Vanilla Rooibos

These three teas illustrate just how much variety there can be within a tea collection.

Earl Grey Special brings lively citrus and floral notes, Earl Grey Cream offers warm vanilla and caramel-inspired aromas, and Madagascar Vanilla Rooibos provides a mellow caffeine-free alternative.

At Brilliant Life Products NZ, we've been bringing a selection of New Zealand beauty, wellness and lifestyle products to customers for more than 15 years.

Whether you're looking for a new breakfast tea, something special to accompany afternoon treats or a fragrant rooibos blend, we invite you to explore our Tea Total collection and find a flavour that feels just right for you.