Convert price per gram to price per kilogram, or calculate unit cost from package price and weight, with per 100 g, ounce, and pound comparisons.
Price Per Gram to Price Per kg Formula
From a package price and weight:
From a known rate per gram:
- Total price — what you paid for the package, in dollars
- Weight in kg — package weight converted to kilograms
- Price per gram — the known unit rate in $/g
Weight conversions used: 1 kg = 1000 g, 1 avoirdupois oz = 0.028349523125 kg, 1 avoirdupois lb = 0.45359237 kg. Troy weights used for precious metals are not supported. The calculation assumes the listed weight is net weight. For drained or dry weight items, use the value printed on the label.
Reference Tables
Quick conversions between the common unit-price labels you see on packaging.
| $ / gram | $ / 100 g | $ / kg | $ / oz | $ / lb |
|---|---|---|---|---|
| $0.001 | $0.10 | $1.00 | $0.028 | $0.45 |
| $0.005 | $0.50 | $5.00 | $0.142 | $2.27 |
| $0.01 | $1.00 | $10.00 | $0.283 | $4.54 |
| $0.05 | $5.00 | $50.00 | $1.42 | $22.68 |
| $0.10 | $10.00 | $100.00 | $2.83 | $45.36 |
| $1.00 | $100.00 | $1,000.00 | $28.35 | $453.59 |
Where each unit shows up most often:
| Unit label | Typical use |
|---|---|
| $/g | Spices, supplements, specialty ingredients, precious metals |
| $/100 g | European and UK grocery shelf labels, nutrition comparisons |
| $/kg | Bulk produce, meat, grains, industrial materials |
| $/oz | US deli items and coffee (avoirdupois ounces; not troy ounces used for bullion) |
| $/lb | US grocery produce and meat counters |
Worked Examples
Example 1. A 500 g bag of coffee costs $8.99. Convert to kg: 500 / 1000 = 0.5 kg. Price per kg = 8.99 / 0.5 = $17.98/kg. Price per gram = 17.98 / 1000 = $0.01798/g.
Example 2. A label shows $0.0125/g. Multiply by 1000: 0.0125 × 1000 = $12.50/kg. That is also $1.25 per 100 g.
Example 3. Comparing two packages: Package A is 250 g for $4.50 ($18.00/kg). Package B is 1.5 lb for $11.99. Convert lb to kg: 1.5 × 0.453592 = 0.6804 kg. 11.99 / 0.6804 = $17.62/kg. Package B is the better value by about $0.38/kg.
Why convert at all? Stores label items inconsistently. Putting everything on a per-kg or per-gram basis is the only way to compare packages of different sizes side by side.
