Coffee is a magical brew that transforms me from a bleary-eyed zombie into a functioning member of society.
I’ve brewed coffee in multiple ways, from the humble French press to the high-tech espresso machine. But there’s one method that’s stolen my heart: the Chemex pour-over.
There’s something about the ritual – the careful measuring, the slow pour – that’s as soothing as it is satisfying.
The key to a great Chemex brew? Mastering your Chemex pour over flow rate. It’s the difference between a decent cup of joe and an ethereal coffee experience that’ll knock your socks off.
I remember my first attempt at a Chemex brew. I poured haphazardly, not paying attention to the rate. The result? A sad, watery, excuse for coffee. Through my trial and error sessions, I learned that taking time to understand and control my flow rate was well worth the effort.
Whether you’re a seasoned coffee connoisseur or a brewing beginner, stick with me. We’ll traverse the landscape of Chemex brewing, from understanding flow rate to finding your ideal coffee-to-water ratio.

What is Chemex Water Flow Rate?
In simple terms, the flow rate is how quickly water is poured onto your fresh coffee grounds.
A good flow rate should be consistent in order to extract the most flavor.
Why Should I Care About My Chemex Flow Rate?
Great question! Here’s the deal:
- Flavor Extraction: The flow rate determines how long the water spends in contact with the coffee grounds. Too fast, and your coffee may taste weak or under-extracted. Too slow, and you risk over-extraction, leading to a bitter taste. We want to hit that sweet spot for the perfect cup of joe!
- Consistency: Once you’ve found your perfect flow rate, sticking to it means you get a consistent brew every time. And who doesn’t want their best cup of coffee day after day?

The Ideal Chemex Pour Over Flow Rate
- About 5 Grams Per Second
Now, don’t let the numbers scare you. It’s simpler than it sounds. The magic number we’re aiming for here is 5 grams per second for your pour over.
We’re not looking for a waterfall cascading over our precious grounds. No, we want a gentle stream, a serene rivulet of hot water meandering its way through the coffee landscape.
The First Pour: Not Too Little, Not Too Much
The first pour is like the first impression – it sets the tone. So, how much water should you use for this all-important first pour? Around 3/5ths or 400 grams, if we’re getting specific.
Now, I know what you’re thinking, “That seems like a lot!” But trust me, it’s just the right amount to get those grounds giddy with excitement and ready to release all their delicious flavors.
Timeframes: A Moment in Time Can Be Full of Flavor
So, you’ve got your water weight and your pour volume. Now, let’s talk timeframes.
Ideally, you want to reach that 400 grams of water in about a minute. Then, give it some time to drain before the next pour. This isn’t a race.
Finally, your brew should be completely drained in around four minutes. Patience is key here, and good things come to those who wait.
- Aim for a flow rate of about 5 grams per second.
- Pour around 400 grams of water for the first pour after blooming.
- Reach this volume within a minute and allow it to drain before the next pour.
- Your brew should be completely drained in about four minutes.

Adjusting Your Brew Speed
So, you’ve tried your hand at brewing with your Chemex and things aren’t going quite as planned? We’ve all been there.
Maybe your brew is too fast or too slow. Either way, I’ve got some tips to help you adjust your brew speed and get that perfect cup.
When Your Brew Speed is Too Fast: Slow it Down
If your water is speeding through your coffee grounds like a race car, leaving you with a weak, under-extracted coffee, don’t panic! Here’s what you can do:
- Finer Grind: Think about it, the smaller the coffee particles, the slower the water will pass through. So, try adjusting your grinder to a finer setting. We’re not aiming for powder here. We still want some texture.
- Slower Pour Rate: If your grind is already fine and you’re still facing a fast brew, consider slowing down your pour rate.
When Your Brew Speed is Too Slow: Speed it Up
On the flip side, if your water is taking its sweet time, lounging around in the coffee grounds, and resulting in an over-extracted, bitter brew, here’s what you can do:
- Coarser Grind: Bigger coffee particles mean faster water flow. So, adjust your grinder to a coarser setting. But be careful, we’re not looking for pebbles.
- Faster Pour Rate: If your grind is already coarse and your brew is still slow, consider pouring a bit faster. But remember, it’s still a gentle pour, not a torrent.

The Golden Coffee-to-Water Ratio: 1:15
The coffee-to-water ratio is exactly what it sounds like – how much coffee you use compared to how much water you pour in. You might be wondering, “Is there a perfect ratio?”
Many coffee connoisseurs swear by the 1:15 ratio. That’s one part coffee to fifteen parts water.
In simpler terms, for every gram of coffee, you use 15 grams of water. This ratio is a fantastic starting point and often leads to a balanced and flavorful pour over brew.
Experimentation: Your Best Friend
Coffee brewing is as much about personal taste as it is about following guidelines. Don’t be afraid to shake things up and experiment.
Maybe you prefer a stronger brew. Try a 1:13 or 1:14 ratio.
Or perhaps you like your coffee a bit on the lighter side? A 1:16 or 1:17 ratio might just hit the spot.
- Start with the 1:15 coffee-to-water ratio.
- Don’t be afraid to experiment with different ratios to find your perfect brew.
Final Thoughts
With a little effort, your Chemex coffee can become so much more than just a cup of joe. Get creative and discover what the perfect brew looks like for you! With practice and patience, you’ll soon be an expert Chemex brewer in no time.
Happy caffeinating!
Frequently Asked Questions
What is the ideal flow rate for a Chemex pour-over?
The ideal flow rate for a Chemex pour-over is around 5 grams per second. This will ensure a balanced extraction and a delicious cup of coffee.
How can I adjust my Chemex brew speed if it’s too fast or slow?
If your brew is too fast, try a finer grind and slower pour. If your brew is too slow, consider a coarser grind and faster pour. Remember, it’s all about finding the right balance for your taste preference.
What is the recommended coffee-to-water ratio for a Chemex pour-over?
Many coffee enthusiasts recommend a 1:15 coffee-to-water ratio for a Chemex pour-over. That’s one part coffee to fifteen parts water. But don’t be afraid to experiment to find your perfect ratio!
How much water should I pour in the first pour when brewing with a Chemex?
The first pour, also known as the “bloom” pour, should typically be twice the weight of the coffee you’re using. For example, if you’re using 30 grams of coffee, your bloom pour should be about 60 grams of water.
How long should it take for my Chemex to finish draining?
The total brew time for a Chemex pour-over should ideally be between 3.5 to 4.5 minutes. If it’s taking significantly longer, your grind may be too fine. If it’s draining too quickly, your grind may be too coarse.