Stock and Broth Ratio Calculator

Homemade stock is built on a ratio of bones or vegetables to water, plus aromatics. Getting the ratio right produces a rich, full-bodied stock. Too much water yields a thin, weak broth; too little leaves you with something over-concentrated.

Standard stock ratios (per quart / liter of finished stock):

The water column is the finished quantity, not what goes in the pot. Read on.

Standard mirepoix (aromatics) per quart / liter:

• Onion: 4 oz / 115g (roughly half a medium onion)
• Carrot: 2 oz / 55g (1 medium carrot)
• Celery: 2 oz / 55g (1 stalk)
• Bay leaf: 1 leaf
• Peppercorns: 4–6 whole
• Thyme: 2–3 sprigs (optional)
• Parsley stems: 4–5 stems (optional)

Yield factor, and it is the thing most stock recipes get wrong

Stock reduces the entire time it simmers. Expect 20–30% evaporation over a 4-hour simmer, which works out at roughly 7% an hour with the lid ajar at a bare simmer. To produce 2 quarts of finished stock you start with about 2.6 quarts of water, and a long beef stock needs proportionally more.

This calculator asks what you want to end up with and works the water backwards from the simmer time. That is the opposite of most stock recipes, which quote a water quantity and leave you to discover the shortfall when you strain it. If you have ever set out to make four quarts and got three, this is why.

Bone broth is the exception worth naming. At 12 to 24 hours a straight evaporation figure would call for absurd quantities of water, so the convention is to start with a normal pot and top it up as the level drops. The calculator caps the loss at half and says so.

Professional technique notes:

1. Start with cold water: this draws impurities out of bones slowly, resulting in a clearer stock
2. Bring to a gentle simmer, never a rolling boil, boiling emulsifies fat and proteins, creating a cloudy, greasy stock
3. Skim the foam during the first 30 minutes, this removes coagulated proteins that cloud the stock
4. Roast bones first for brown stock, roasting at 400°F / 200°C for 45 minutes before simmering creates deep color and flavor
5. Strain through a fine-mesh strainer, then cool rapidly in an ice bath before refrigerating

Storage:

• Refrigerator: 4–5 days
• Freezer: 3–6 months (freeze in 1-cup / 240 mL portions for convenience)
• Fat cap: Refrigerated stock forms a solid fat layer on top: leave it on until use (it acts as a natural seal)