How do I make coffee stronger?

"Stronger" is used for two different things: coffee that tastes more intense, and coffee with more caffeine. Both are mostly controlled by dose — how much coffee you use — not by brewing harder. Extending the brew or grinding finer makes coffee more extracted, which past a point means bitter, not strong.

What you'll need

• Kitchen scales
• Your usual brewing equipment

Step by step

1. Weigh what you currently use, so you have a baseline.Scoops vary hugely with grind size and bean density. Weight is the only reliable measure.
2. Work out your current ratio in grams per litre.A standard starting point is 60g/litre. Many people are unknowingly at 40 or below, which is the real cause of weak coffee.
3. Increase the dose to 65–70g per litre, keeping grind, time and temperature unchanged.One variable at a time. This alone makes most 'weak' coffee taste right.
4. Taste. If it's stronger but not bitter, you've found the fix.If it's now bitter, you've gone past extraction — coarsen the grind slightly to compensate.
5. If you want more intensity again, keep increasing the dose in small steps.Ratios up to about 75–80g/litre are still perfectly drinkable for many people.
6. Don't extend the brew time to compensate.Longer contact extracts more from the same grounds — that's the route to bitterness, not strength.
7. If you want more caffeine specifically, use more coffee or a lighter roast.Contrary to expectation, dark roast is not higher in caffeine — the difference by weight is small and slightly favours lighter roasts.

Tips

• Scales cost very little and change coffee more than any other purchase at that price. Everything else is guesswork without them.
• If you want a strong flavour without more caffeine, look for a darker roast or a bean with more body rather than increasing the dose.
• Espresso isn't higher in caffeine per serving than filter — it's much more concentrated, but a single shot is a much smaller volume than a mug of filter.
• Milk mutes perceived strength considerably. Coffee that tastes right black will often taste weak with a lot of milk, and needs a higher dose.

Common mistakes

• Grinding finer to get strength — That increases extraction, not concentration. Past a point it's just bitter.
• Brewing for longer — Same problem — you're extracting more from the same grounds, not adding coffee.
• Measuring by scoop — A scoop of coarse grounds and a scoop of fine grounds differ substantially in weight.
• Assuming dark roast means more caffeine — It doesn't. If anything, lighter roasts are marginally higher by weight.

Questions people ask