Cold Brew Coffee Dilution Calculator
Calculate cold brew water and coffee for concentrate vs ready-to-drink.
Get dilution ratios, brew time targets, and final caffeine concentration estimates.
Cold Brew Coffee Dilution
Cold brew uses long steep times and cold water to extract a smooth, low-acid coffee. Two main styles:
1. Concentrate (1:4 to 1:8 ratio) — meant to be diluted with water, milk, or mixers 2. Ready-to-drink (1:10 to 1:15 ratio) — pour over ice, no dilution needed
Standard recipes:
| Style | Coffee:Water | Steep Time | Yield |
|---|---|---|---|
| Strong concentrate | 1:4 | 16-20 hours | Dilute 1:1 to drink |
| Standard concentrate | 1:5 | 14-18 hours | Dilute 1:1 to drink |
| Mild concentrate | 1:8 | 12-16 hours | Dilute 1:0.5 to drink |
| Ready-to-drink | 1:10 | 10-14 hours | Drink as-is |
| Light Japanese-style | 1:15 | 8-12 hours | Drink as-is |
Dilution rule of thumb: Concentrate ratio (1:N) → drink at 1:(2N) ratio
So 1:5 concentrate diluted 1:1 with water = 1:10 final ready-to-drink strength.
Caffeine content estimates:
- Standard concentrate (1:5): ~150-200 mg / fluid oz
- Diluted (1:10): ~75-100 mg / fluid oz
- Ready-to-drink (1:10): ~75-100 mg / fluid oz
- Light Japanese-style (1:15): ~50-70 mg / fluid oz
A 12 oz iced coffee from concentrate (1:5 + 1:1 dilution):
- 6 oz concentrate + 6 oz water/milk
- Caffeine: ~900-1,200 mg total — roughly 4-5× a standard hot coffee
Dilution math: Final volume = Coffee × N × (1 + dilution factor)
Example: 100 g coffee at 1:5 ratio = 500 g concentrate
- 1:1 dilution = 1,000 g final beverage
- 1:0.5 dilution = 750 g final beverage
Brewing tips:
- Use coarse grind (coarser than French press) — fine grinds make muddy concentrate
- Filter twice: paper filter after the steep, then chill 4-6 hours for crystal-clear yield
- Refrigerate concentrate up to 2 weeks
- Diluted batches drop in flavor after 5-7 days
Why cold brew is smoother: Cold water doesn’t extract chlorogenic acids efficiently. The result: 60-70% less perceived acidity vs. iced hot-brewed coffee, with a sweeter, fuller mouthfeel — but you also miss some flavor compounds that only emerge above 90°C.