Mash Water Calculator
Calculate strike water temperature and sparge volumes for all-grain brewing. Hit your target mash temperature every time.
Grain Bill
Mash Settings
Sparge & Boil
Strike Water
Strike Water Volume
3.13 gal
Total Water Needed
7.06 gal
First Runnings
2.56 gal
Post-Boil Volume
5.5 gal
Mash Details
Sparge Water
Heat sparge water to 168-170°F (75-77°C) to help with lautering and prevent tannin extraction.
Brew Day Summary
Mash Tips
- • Preheat your mash tun to reduce heat loss
- • Stir well when adding grain to avoid dough balls
- • Lower mash temps = more fermentable, drier beer
- • Higher mash temps = more body, sweeter beer
- • Check actual mash temp after mixing and adjust
Mash Temperature Guide
Mash temperature determines the fermentability of your wort. Lower temps produce more fermentable sugars (drier beer), higher temps produce more unfermentable sugars (fuller body, sweeter beer).
Beta Amylase Rest
Balanced Range
Alpha Amylase Rest
Sparging Methods
Batch Sparge
- • Drain mash tun completely
- • Add sparge water, stir
- • Let settle 10 minutes
- • Drain again
- • Repeat if doing 2+ batches
- • Simpler equipment
Fly Sparge
- • Continuous water addition
- • Match runoff with inflow
- • Takes 60-90 minutes
- • Slightly higher efficiency
- • Requires sparge arm
- • Traditional method
No Sparge (BIAB)
- • All water in mash
- • Lift and drain bag
- • Squeeze optional
- • Lower efficiency (~70%)
- • Use more grain
- • Simplest method
Frequently Asked Questions
Why is my mash temperature different than expected?
Several factors affect final mash temp: grain temperature (cold grain from storage lowers temp more), mash tun pre-heating (or lack of), water temp measurement accuracy, and thermal mass of equipment. Always verify mash temp after mixing and adjust with hot/cold water if needed.
What mash thickness should I use?
Standard mash thickness is 1.25-1.5 qt/lb. Thinner mashes (1.5-2 qt/lb) improve enzyme activity and extraction but may need larger vessels. Thicker mashes (1-1.25 qt/lb) retain heat better and may improve body. BIAB typically uses 2+ qt/lb.
Should I batch sparge or fly sparge?
Batch sparging is simpler, faster, and nearly as efficient (85-90% vs 90-95% for fly). It requires less equipment and is more forgiving. Fly sparging extracts slightly more sugar but takes longer and requires careful flow rate control to prevent channeling and tannin extraction.
What temperature should sparge water be?
Heat sparge water to 168-170°F (75-77°C). This helps extract remaining sugars and improves flow. Avoid exceeding 175°F (80°C) which can extract harsh tannins from grain husks. The grain bed will cool the water as it flows through.
How much water do grains absorb?
Standard absorption is about 0.125 gallons (0.5L) per pound of grain. Fine crush absorbs less (~0.1 gal/lb), coarse crush absorbs more. BIAB with squeezing reduces absorption to 0.08-0.1 gal/lb. This calculator accounts for absorption in volume calculations.
What's the strike water temperature formula?
Strike Temp = (0.2/R) × (T2 - T1) + T2, where R is water:grain ratio (qt/lb), T1 is grain temp, T2 is target mash temp. The 0.2 represents the thermal mass ratio of grain to water. This calculator uses this formula.
Related Calculators
Found this calculator helpful?
Check out our other free calculators for everyday math problems.
View All Calculators