What is PPG (Points Per Gallon)?

PPG (Points Per Pound Per Gallon) is a measure of how much fermentable sugar a grain contributes per pound per gallon. Pale malt is typically 36-37 PPG, while crystal malts range from 33-35 PPG.

What efficiency should I use?

Most homebrewers achieve 65-80% brewhouse efficiency. BIAB (Brew In A Bag) systems typically see 70-80%, while traditional 3-vessel setups get 72-78%. Track your actual efficiency over several brews to dial in your number.

How do I calculate OG with multiple grains?

Add each grain separately using its own PPG value, then total them. This calculator uses a single average PPG. For detailed multi-grain calculations, use a recipe design tool.

Why is my actual OG different from predicted?

Common causes include: inaccurate grain crush, mash temperature or time issues, poor sparging technique, or using a different efficiency than your system actually achieves. Calibrate based on actual brew day results.

Can I use this calculator for extract brewing?

For extract brewing, use our Malt Extract Calculator instead. Extract brewing bypasses the mash, so efficiency does not apply. With extract, you get close to 100% of the listed PPG since the sugars are already dissolved.

BrewCalcs

Original Gravity Calculator — Estimate OG

Estimate your original gravity from grain bill weight, potential extract and brewhouse efficiency.

Total Grain Weight

Total weight of grain in your recipe

Average PPG

Points per pound per gallon (e.g. Pale Malt = 37)

Brewhouse Efficiency

Your system mash efficiency percentage

Batch Size

Volume of your batch

How We Calculate This

The OG Formula

Original gravity is estimated using: OG = 1 + (grain_lbs x PPG x efficiency) / (batch_gallons x 1000). The grain weight is converted to pounds, multiplied by the potential extract (PPG) and your efficiency percentage, then divided by the batch volume in gallons.

Understanding PPG

PPG stands for Points Per Pound Per Gallon. Common values: Pale Malt 36-37, Munich 34-35, Crystal 33-35, Wheat 36-37, Pilsner 36-37. These represent the maximum extract potential of each grain.

Frequently Asked Questions

Related Calculators

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Convert Brix refractometer readings to specific gravity.

Plato to SG Converter

Convert degrees Plato to specific gravity and back.

Attenuation Calculator

Calculate apparent and real attenuation of your fermentation.

Last updated: 2025-02-20

All calculations are estimates. Always verify values and adjust based on your equipment and ingredients.