Bitterness is usually a sign of over-extraction — too much has been pulled out of the grounds relative to how much water and time was used.
Common causes
- Grind too fine for your brew method, which extracts too quickly and too much
- Water too hot, especially above 205°F (96°C)
- Brewing too long, letting the water sit in contact with grounds past the ideal window
- Stale or over-roasted beans, which taste bitter regardless of technique
How to fix it
- Coarsen your grind slightly and brew again.
- Check your water temperature — just off the boil is usually too hot.
- Shorten your brew or steep time.
- Check your roast date; coffee is best within a few weeks of roasting.
If your coffee tastes weak and bitter at the same time, your ratio may be off — start with our coffee-to-water ratio guide before troubleshooting further.
