RISE Sleep Tracker
One of Apple's Best Apps of 2024
★★★★★
(20,627)
TRY FREE

How Long Does Caffeine Last? This App Calculates It For You

Caffeine may last more than 12 hours, but it all depends on your genetics, age, lifestyle, and how much caffeine you have each day.
Published
2022-05-18
Updated
2023-12-22
19 MINS
Written by
Jeff Kahn, M.S., Rise Science Co-Founder
Reviewed by
Chester Wu, MD, Rise Science Medical Reviewer
Our Editorial Standards
We bring sleep research out of the lab and into your life. Every post begins with peer-reviewed studies — not third-party sources — to make sure we only share advice that can be defended to a room full of sleep scientists.
Learn more
Updated Regularly
We regularly update our articles to explain the latest research and shifts in scientific consensus in a simple and actionable way.
Woman drinking coffee

How Long Does Caffeine Last? It’s Longer Than You Think 

  • Caffeine can last in your system for more than 12 hours. 
  • How long caffeine lasts depends on factors like your age, metabolism, whether you take medication or smoke, and how much caffeine you’ve had that day. 
  • To make sure caffeine doesn’t last into the night and keep you awake, the RISE app calculates when you should stop drinking coffee each day based on your body clock.

Coffee is great in the morning to kickstart the day. But it’s not so great at night when you’re left wide awake and struggling to sleep. 

So how long does caffeine stay in your system? Unfortunately, that’s not a straightforward question. 

Caffeine affects us all differently and how long it lasts will depend on your age, metabolism, and how much caffeine you have — just to name a few factors. 

Below, we’ll dive into how long caffeine typically lasts and how you can enjoy coffee and sleep.

We Asked a Sleep Doctor:

Before we dive into the science, what are Rise Science sleep advisor and medical reviewer, Dr. Chester Wu's thoughts on caffeine and sleep?

“Caffeine lasts longer than you think. It can stay in your system for more than 12 hours, so an afternoon coffee could keep you awake at bedtime or disrupt your sleep during the night. You don’t have to give up coffee altogether, though. Enjoy caffeine in the morning and switch to decaf or caffeine-free drinks around lunchtime.”

How Long Does Caffeine Last?

Caffeine can last for more than 12 hours in your system. But the exact amount of time will look different for everyone, and it may even change for you from day to day depending on how much caffeine you consume. How long caffeine lasts in your system and how long the effects — like increased alertness — last can be different, too. 

Let’s dive into how long caffeine lasts in more detail. 

How Long Does Caffeine Last in Your System? 

In general, caffeine lasts in your system for more than 12 hours. But the amount of time caffeine lasts depends on: 

  • Age: Older adults may metabolize caffeine slower than younger adults, so it may last longer. 
  • Genetics: Caffeine binds to adenosine receptors in your brain. If you’ve got “sticky” receptors, caffeine can last longer. Genetics also affects how quickly your liver breaks down caffeine. The quicker your liver can break caffeine down, the quicker it will wear off. How long it takes it to metabolize caffeine will be different for everyone. Genetics also influences whether caffeine causes sleep problems and anxiety, too.
  • Whether you’re a regular coffee drinker: If you don’t usually drink coffee, you may feel the effects more strongly and for longer. 
  • If you’re taking any medication: Medications can change the half-life of caffeine. This is how long it takes the amount of caffeine in your system to decrease by half. Oral contraceptives, for example, double the half-life, meaning caffeine will last longer.  
  • Whether you’re a smoker: Nicotine cuts the half-life of caffeine by 50%.
  • Your caffeine intake that day: The more caffeine you have, the longer it’ll last in your system. Four double-shot espressos will last longer than a single-shot latte.

What’s the Half-Life of Caffeine? 

A single dose of caffeine has a half-life of three to seven hours. This means it takes three to seven hours for the amount of caffeine in your system to decrease by half. 

Let’s say the half-life of caffeine is five hours for you. That would mean if you had 100 milligrams of caffeine at 12 p.m., there would be 50 mg in your system at 5 p.m. and 25 mg by 10 p.m., and so on. 

Caffeine’s half-life can be different for everyone and it may be longer if you have more caffeine. This means the time it takes your body to clear half of the caffeine in your system can vary. And don’t be fooled into thinking 50% of the caffeine isn’t much — it can still disrupt your sleep.

How Long Do Caffeine Effects Last? 

Caffeine’s effects may last for more than 12 hours. But this number will be different for everyone depending on how your body reacts to caffeine. And different caffeine effects may last for different amounts of time. 

A 2021 meta-analysis found caffeine may improve your: 

  • Energy 
  • Mood
  • Cognitive functions (like attention)
  • Memory  
  • Reaction time 

But it’s not yet clear how long these individual effects can last. 

For example, when it comes to memory, caffeine’s effects can be seen after 24 hours. In one study, participants who had 200 mg of caffeine performed better on a memory test 24 hours later compared to those who had a placebo. 

When it comes to reaction time, on the other hand, caffeine’s effects may diminish quickly. In one study, consuming a 6 mg/kg dose of caffeine (equivalent to 408 mg for a 150 pound individual) 90 minutes before a visual reaction test did not speed up reaction times as expected. It was theorized that caffeine might have been consumed too early in relation to peak plasma levels (estimated at 60 minutes after supplementation) and thus caffeine’s effects with regards to reaction time would have been limited due to incorrect timing.

How long caffeine can keep you awake will be different for everyone and depend on many factors, like how much caffeine you have, how sleep deprived you are, and your genetics. 

A study that administered 200 mg of caffeine 16 hours prior to bedtime found that even with a large time gap and low blood levels of caffeine, caffeine’s impact on sleep was still noticeable. 

On the other hand, you may also develop a tolerance to caffeine, meaning some effects from your regular dose won’t last for very long or at all. 

How Long Does a Cup of Coffee Last? 

How long a cup of coffee lasts depends on how much caffeine is in the coffee and on factors like your age, metabolism, and genetics. 

In general, caffeine can stay in your system for more than 12 hours and it has a half-life of three to seven hours. 

There are about 95 milligrams of caffeine in an 8-ounce cup of brewed coffee. So after five hours (if that’s caffeine’s half-life for you), half of that — 47.5 mg — would still be in your system. After another five hours, 24 mg of caffeine would be in your system.

The caffeine content of a “cup” of coffee can vary widely. Cup sizes can be very different and the amount of caffeine in a particular cup size depends on the coffee beans and how they’re brewed.

One “cup” of instant coffee can contain 30 mg to 90 mg, but a venti 20-ounce cup of coffee from Starbucks can contain about 410 mg of caffeine.  

The more caffeine a cup of coffee has, the longer it’ll last in your body.

{{ cta }}

When Should I Stop Drinking Coffee Each Day?

Stop drinking coffee about 12 hours before bed — or even earlier if you find you’re sensitive to it. This should give your body enough time to break down all the caffeine in your system, so it doesn’t keep you up. 

That 12-hour mark is just an estimate, though. 

Caffeine affects us all differently, so there’s no one agreed-upon caffeine elimination time. Different studies share different recommendations. 

And when you need to stop drinking coffee may be different from when you need to stop drinking energy drinks or avoid taking a pre-workout supplement — both of which often can contain more caffeine than a cup of coffee. 

Research from 2023 states you should avoid coffee at least nine hours before bed and pre-workout at least 13 hours before bed to avoid reducing your sleep time. 

RISE acts as a caffeine calculator and gives you an exact caffeine cutoff time that’s tailored to you each day. 

To give you a caffeine cutoff time, RISE predicts the timing of your circadian rhythm, or body clock, based on factors like your inferred light exposure and last night’s sleep times. 

As part of your circadian rhythm, you’ll see your Melatonin Window in the RISE app. This is what we call the roughly one-hour window of time when your body’s rate of melatonin is at its highest. Melatonin is your sleep hormone, so your Melatonin Window is the ideal time to head to bed. The timing of your Melatonin Window can shift each day depending on your sleep times. 

Each day, RISE sends you a reminder to limit caffeine 10 hours before your Melatonin Window that night. You can adjust the timing of this reminder if you find you’re more or less sensitive to caffeine.

Most people’s cutoff time will be around noon. Night owls may be able to drink caffeine a little later into the day, until around 2 p.m. As with everything to do with caffeine, this will be individual to you and depend on many factors. 

We’ve covered more advice on when to stop drinking coffee here.

RISE app screenshot showing when to limit caffeine intake
The RISE app can tell you when to stop drinking coffee each day.

RISE users on iOS 1.202 and above can set up their limit caffeine reminder here.

How Late Is Too Late to Drink Coffee?

There’s no hard-and-fast rule for how late is too late to drink coffee. The time will be different for everyone. But, in general, you want to avoid caffeine about 12 hours before bed.

Caffeine can disrupt your sleep, even if you stop drinking it hours before trying to sleep. 

One study gave participants 400 mg of caffeine zero, three, or six hours before bed to compare the differences. The results showed each of these caffeine times disrupted sleep. That included those who had caffeine six hours before bed — their sleep time was reduced by more than one hour compared to those who had taken a placebo. 

And caffeine can do more than just keep you awake. 

Research from 2023 shows caffeine can reduce your total sleep time, increase how long you’re awake during the night, increase the amount of light sleep you get, and decrease the amount of deep sleep you get.

How Much Caffeine is Too Much?

In general, anything more than 400 milligrams of caffeine a day is too much. 

The US Food and Drug Administration (FDA) recommends consuming a maximum of 400 mg of caffeine a day. 

If you drink energy drinks, it’s recommended you stick to one can of energy drink per day.

Research suggests 300 mg of caffeine a day isn't linked to adverse health effects in healthy adults. But this may be too much for some people. 

If you’re sensitive to caffeine or have a health condition like high blood pressure, you might want to consume less caffeine than this — or none at all. 

And if you’re pregnant or breastfeeding, The American College of Obstetricians and Gynecologists, recommends you stick to less than 200 milligrams of caffeine a day. Speak to your healthcare provider to make sure it’s okay for you to consume caffeine and get personalized advice on how much. 

Too much caffeine can lead to side effects such as: 

  • Anxiety 
  • Trouble sleeping 
  • Jitters
  • Dizziness
  • Headaches
  • Migraines 
  • Stomach problems 
  • Increased heart rate 
  • Dependency and tolerance (you need more coffee to feel the same effects) 

If you become dependent on caffeine and don’t have it, you may experience withdrawal symptoms. Caffeine withdrawal symptoms include: 

  • Tiredness
  • Muscle pain 
  • Irritability 
  • Difficulty concentrating 

When you consume caffeine is just as important as how much you consume. Sure, 400 mg spread across the morning may be okay. But it’s a different story if you have 400 mg of caffeine in the late afternoon or evening. 

In general, avoid caffeine about 12 hours before bed to make sure it doesn’t keep you up or check RISE for your daily caffeine cutoff recommendation.

You can learn more about how much caffeine is too much here.

How Long Does it Take Caffeine to Kick in?

It can take 15 minutes to two hours for caffeine to fully kick in and reach peak levels in your system, so you may feel the stimulating effects of caffeine fast. Caffeine is completely absorbed by your body in 45 minutes. 

How long it takes caffeine to kick in will be different for each person, though. 

How Can I Stop Caffeine From Affecting My Sleep?

Here’s how you can stop caffeine from affecting your sleep: 

  • Stop consuming caffeine about 12 hours before bed (or check RISE for the exact time)
  • Limit your caffeine consumption to 400 mg or less each day (through a gradual taper)
  • Watch out for hidden caffeine in green tea, hot chocolate, kola nuts, yerba mate, decaf coffee, and some pain relievers and cold medications  

How long caffeine affects your sleep will depend on factors like how much caffeine you have and your genetics. 

Caffeine doesn’t just keep you awake, though. A 2023 meta-analysis found caffeine can: 

  • Reduce total sleep time by 45 minutes
  • Increase how long it takes you to fall asleep by nine minutes
  • Increase the time you’re awake during the night by 12 minutes 
  • Increase the amount of light sleep you get
  • Decrease the amount of deep sleep you get 

So sticking to that all-important caffeine cutoff time can improve your whole night of sleep, which will improve your energy levels the next day. 

Need a caffeine-free pick-me-up? We’ve covered how to get energy without caffeine here.

Why Doesn’t Caffeine Work For Me?

If you feel like caffeine isn’t working for you, or doesn’t work for long, there are a few reasons that could be to blame: 

  • You’ve got high sleep debt: This is the amount of sleep you’ve missed out on recently. There’s only so much sleep debt caffeine can mask, so if you’ve missed out on a lot of sleep recently, caffeine may not be boosting your energy anymore. 
  • You’re in a dip in your circadian rhythm: This is your roughly 24-hour body clock. It dictates how your energy levels fluctuate throughout the day. The afternoon dip in energy we all get may override any caffeine you consume. This dip in energy will feel lower if you’ve got a lot of sleep debt. 
  • You’ve developed a caffeine tolerance: You may need more caffeine than usual to feel the same effects. 
  • Genetics: Some people are simply less sensitive to caffeine and find it doesn’t give them much of a boost. 

{{ video }}

Sometimes caffeine can work, but it leaves you feeling more tired than before. That could be due to:

  • A sugar crash (if you’ve added sugar or syrup to your coffee or you’re drinking a sugary energy drink).
  • Caffeine-induced sleep loss, making you more tired the next day. 
  • Feeling the sleepiness effects of sleep debt and a circadian dip in energy when caffeine wears off. 
  • Having less caffeine than usual and experiencing caffeine withdrawal symptoms

We’ve covered more reasons why caffeine makes you tired here and why caffeine doesn’t affect you here.

To rule out sleep debt, you can use RISE to find out if you’ve got any sleep debt and how much sleep you should be aiming for each night. The app also predicts the timing of your circadian rhythm each day, so you can see when your energy is expected to dip.

RISE app screenshot showing how much sleep debt you have
The RISE app tells you whether you’ve got any sleep debt each day.

Heads-up: You may need more sleep than you think. We looked at how much sleep 1.95 million RISE users aged  24 and up need. It ranged from five hours a night to a whopping 11 hours 30 minutes a night. The median was eight hours. 

RISE works out how much sleep you need using a year’s worth of your phone use data and proprietary sleep-science-based models. You’ll know how much sleep to aim for each night, so you don’t need to rely on caffeine for energy.

We looked at how much sleep 1.95 million RISE users aged  24 and up need. It ranged from five hours a night to a whopping 11 hours 30 minutes a night. The median was eight hours.
The RISE app can work out how much sleep you need.


RISE users on iOS 1.202 and above can click view their sleep need here and view their sleep debt here.

{{ cta-mini }}

How to Get Caffeine to Wear Off?

It’s hard to get caffeine out of your system faster. 

If you’ve had too much caffeine and you’re feeling jittery or anxious, you can reduce caffeine’s side effects by: 

  • Drinking water
  • Doing some exercise
  • Taking some deep breaths  

If you’ve had caffeine too close to bedtime and you’re struggling to sleep, you can try to make yourself tired by:  

  • Doing a relaxation exercise like progressive muscle relaxation (RISE can guide you through this in the app). 
  • Making sure your bedroom is cool, dark, and quiet, so you’re set up for sleep.
  • Getting out of bed (after 20 minutes of trying to sleep) and doing a relaxing activity like reading with the lights dimmed as low as possible. Only head back to bed when you start feeling sleepy. 

Remember to make a mental note of how much caffeine you had or how close to bedtime you had it so you don’t make the same mistake twice.

How Does Caffeine Work?

Caffeine works by stopping adenosine (a chemical that makes us feel sleepy) from working in our brains.  

Here’s a quick biology lesson.

When you ingest caffeine, enzymes in your liver break it down, metabolizing it into paraxanthine and theophylline. These compounds temporarily block the A1 and A2 adenosine receptors in your brain. 

Adenosine is a natural chemical that builds up in your system the longer you’re awake, making you feel sleepy over time. But if adenosine can’t bind to your receptors — because paraxanthine and theophylline are there instead — you won’t feel the sleepiness it causes.

Caffeine doesn’t just block adenosine, though. It stimulates your central nervous system and triggers the release of adrenaline, giving you a mental and physical energy boost. Caffeine makes us feel more alert and increases attention, reaction times, and memory.

Want to learn more? We’ve answered all of your sleep and caffeine questions in one place.

What Contains Caffeine?

Caffeine can be found in coffee, tea, energy drinks, soft drinks, and chocolate. 

How much caffeine these foods and drinks contain depends on the type of coffee beans or tea leaves, how they’re made, and the serving size. 

Here are the typical caffeine levels in common foods and drinks:  

  • Brewed coffee — about 95 milligrams of caffeine per 8-ounce cup 
  • A single shot of espresso — about 63 mg 
  • One cup of instant coffee — 30 mg to 90 mg 
  • Decaffeinated coffee — 3 mg to 12 mg (it all depends on the decaffeination method)  
  • Soft drinks like Coke — 21 mg per 7.5-ounce can  
  • Black tea — 47 mg to 90 mg per 8-ounce cup 
  • Green tea — 20 mg to 45 mg per 8-ounce cup 
  • Energy drink — 50 mg to 160 mg  
  • Milk chocolate — 9 mg per 1.55 ounces 
  • Dark chocolate — 12 mg per ounce 

Fall Asleep Easily, Even if You Drink Coffee 

Caffeine can last for more than 12 hours, but this can depend on your age, metabolism, and how much caffeine you have — and that’s just for starters.  

RISE can make things simple by giving you an exact time to stop drinking coffee (or any other caffeinated beverage) each day. This time is based on your circadian rhythm and can be tailored if you find you’re more or less sensitive to caffeine. 

When you know your caffeine cutoff time, you can enjoy coffee in the morning, cut yourself off when RISE tells you to, and give your body plenty of time to break down the caffeine you’ve had before bedtime.  

We found 80% of RISE users get more sleep within five days, so you don’t have to choose between caffeine and a good night’s sleep.

FAQs

How long can it take for coffee to wear off?

It can take more than 12 hours for coffee to wear off. How long it takes for coffee to wear off depends on factors like your age, metabolism, and how much caffeine you’ve had. The half-life of caffeine is three to seven hours. This is how long it takes half of the caffeine in your system to clear. So caffeine can last for a different amount of time for everyone.

How long does caffeine affect sleep?

Caffeine may affect your sleep more than 12 hours after you’ve consumed it as it can last in your system for more than 12 hours. Caffeine can keep you awake, wake you up in the night, and reduce the amount of deep sleep you get. Aim to avoid caffeine about 12 hours before bed to stop it from disrupting your sleep.

How long does 100mg of caffeine last?

The half-life of caffeine can be anywhere from three to seven hours. So, if you drink 100 mg of caffeine, you'd still have 50 mg in your system about five hours later, and 25 mg about 10 hours later. It can take more than 12 hours for caffeine to leave your system, so aim to avoid caffeine about 12 hours before bedtime.

How long does 200mg of caffeine last?

The half-life of caffeine can be anywhere from three to seven hours. So, if you drink 200 mg of caffeine, you'd still have 100 mg in your system about five hours later, and 50 mg about 10 hours later. It can take up to 12 hours for caffeine to leave your system, so aim to avoid caffeine about 12 hours before bedtime.

How long does 300mg of caffeine stay in your system?

The half-life of caffeine can be anywhere from three to seven hours. So, if you drink 300 mg of caffeine, you'd still have 150 mg in your system about five hours later, and 75 mg about 10 hours later. It can take up to 12 hours for caffeine to leave your system, so aim to avoid caffeine about 12 hours before bedtime.

How long does caffeine last calculator?

Caffeine can last for more than 12 hours, but this depends on your age, metabolism, whether you take medication, and how much caffeine you’ve had. RISE is a caffeine calculator that tells you when to stop consuming caffeine each day to stop it from keeping you awake at night.

Sleep better. Sell more.

Learn more about Rise for sales teams.

Thanks! We received your information. You'll hear from us shortly.
Oops! Something went wrong while submitting the form.
About Rise
Rise is the only app that unlocks the real-world benefits of better sleep.

Instead of just promising a better night, we use 100 years of sleep science to help you pay down sleep debt and take advantage of your circadian rhythm to be your best.

Over the past decade, we've helped professional athletes, startups, and Fortune 500s improve their sleep to measurably win more in the real-world scenarios that matter most.

Rise Science is backed by True Ventures, Freestyle Capital, and High Alpha; investors behind category winners Fitbit, Peloton, and Salesforce Marketing Cloud.

Sleep Hygiene

View all
Try 7 days free

The power behind your next best day

RISE makes it easy to improve your sleep and daily energy to reach your potential

RISE app iconApp store icon