How to Use This Calculator
This tool answers the real question every home miller asks: "Is milling my own flour actually saving me money — and how long until my mill pays for itself?"
- Pick your grain type — each has a slightly different volume yield ratio (explained below).
- Enter your actual prices — what you pay per pound for bulk berries and for comparable store flour.
- Add your mill's wattage and local electricity rate to include the (usually tiny) energy cost.
- Set your monthly flour usage and mill price to see annual savings and payback timeline.
- Use the storage planner to figure out how many pounds of grain to keep on hand and how many buckets you need.
Understanding the Volume vs Weight Rule
This is the most common source of confusion for new home millers. By weight, 1 lb of whole wheat berries always yields 1 lb of flour — because home milling grinds the entire berry (bran, germ, and endosperm) with nothing discarded. Nothing is lost. The cost comparison is therefore straightforward: price per pound of berries vs. price per pound of comparable flour.
By volume, 1 cup of berries yields more than 1 cup of flour because milling aerates and "fluffs" the grain. The expansion ratio varies by grain type:
- Hard red / hard white wheat — the workhorse. Follows the standard ~1:1.5 ratio closely (1 cup berries → ~1½ cups flour).
- Soft white wheat — lower protein, starchier. Mills into very fine, powdery flour; can expand to 1:1.65–1.75.
- Einkorn — small, dense ancient grain. Doesn't expand as much; closer to 1:1.25–1.4.
- Spelt — similar to hard wheat, around 1:1.5; slightly more brittle.
- Rye — leaner, denser flour; stays closer to 1:1.25–1.3.
If your recipe gives amounts in cups, use the volume ratio. If it gives amounts in grams or ounces, just use the same weight of berries — no conversion needed.
Worked Example
Setup: Hard white wheat berries at $1.20/lb; King Arthur organic whole wheat flour at $2.20/lb; 450W stone mill; $0.15/kWh electricity; 10 lb flour per month; $350 mill.
Milled cost/lb: $1.20 (berries) + ~$0.001 (electricity) ≈ $1.20/lb
Savings/lb: $2.20 − $1.20 = $1.00/lb
Annual savings: $1.00 × 10 lb/month × 12 = $120/year
Mill payback: $350 ÷ $120/yr ≈ 35 months (~2.9 years)
Switch to a premium specialty flour comparison (e.g., einkorn flour at $5+/lb vs einkorn berries at ~$2.50/lb) and payback drops to under a year.
Tips for Maximising Savings
- Buy berries in bulk (25–50 lb bags). Per-pound price drops significantly compared to small bags.
- Compare apples to apples. Budget-bin white all-purpose flour vs. organic wheat berries is an unfair comparison. Compare organic whole wheat flour vs. organic whole wheat berries for an accurate picture.
- Include shipping costs when calculating berry price — especially for smaller orders. Enter the all-in landed price per pound.
- The savings are bigger for specialty grains. Einkorn, spelt, kamut, and rye flour at retail can be 2–5× the price of the berries — so the payback period on specialty bakers is much shorter.
- Time value. Milling typically takes 5–10 minutes per batch. Factor in whether that time is worth the savings to you personally.
Frequently Asked Questions
Does 1 pound of wheat berries really yield 1 pound of flour?
Yes, by weight. Home milling grinds the complete berry — bran, germ, and endosperm — so nothing is discarded. One pound of berries becomes one pound of whole-grain flour. Volume increases because milling aerates the grain, but mass is conserved. This makes the cost comparison simple: price per pound of berries equals cost per pound of flour (before electricity).
How many cups of flour does 1 cup of wheat berries make?
It varies by grain type. Hard red and hard white wheat yield approximately 1½ cups of flour per cup of berries — the standard "1:1.5" rule of thumb. Soft white wheat can produce 1.65–1.75 cups because it mills into very fine, airy flour. Einkorn, a smaller and denser ancient grain, stays closer to 1.25–1.4 cups. Rye is similar to einkorn at 1.25–1.3. Spelt behaves similarly to hard wheat. For recipe accuracy, weighing is always more reliable than measuring by volume.
How long until a grain mill pays for itself?
It depends on your savings per pound and how much flour you mill. A family milling 10 lb/month saving $1.00/lb earns back $120/year — a $350 mill pays off in about 35 months. Mill more flour or choose specialty grains with larger price gaps and the payback shrinks dramatically. A heavy baker (20+ lb/month) comparing premium organic flours can sometimes break even in under 12 months.
Does electricity cost significantly affect the savings?
No — it's almost negligible. A 1200W impact mill milling 10 lb of grain takes roughly 5 minutes, consuming about 0.1 kWh, which costs ~$0.015 at a typical US rate. A slower 450W stone mill for the same batch uses even less. Over a full year of regular milling, electricity might add $1–4 to total costs — far less than 1% of typical savings.
Can I mill grains other than wheat?
Yes — most stone and impact mills can handle rye, spelt, einkorn, kamut/khorasan, barley, oat groats (dehulled), millet, buckwheat, quinoa, amaranth, sorghum, dried corn, and most dry legumes (chickpeas, lentils, split peas, etc.). Avoid oily seeds (flax, sesame, sunflower, chia), nuts, coffee, herbs, or sprouted grains unless your specific mill's manual explicitly permits them. Always check your mill's documentation before trying a new ingredient.
Is home-milled flour the same as store-bought whole wheat flour?
It's similar but fresher. Home-milled flour contains 100% of the grain — bran, germ, and endosperm — with all natural oils and vitamins intact. Store-bought "whole wheat" flour often has some of the germ removed for shelf stability, and even when the full kernel is used, the milling happened weeks or months before purchase. Freshly milled flour is higher in nutrients and flavor but also has a shorter shelf life (refrigerate or freeze within a few days of milling).