Quintals, tonnes, cases and gross; comparing packs by price per kg or litre; and pricing after loss in handling.
By Manoj Sahukar· October 2026 · 6 min read
How numbers are rounded on these pages. Calculations are done at full precision and rounded only at the end, half up. Rupee amounts are rounded to the nearest rupee unless shown with paise, in which case to the nearest paisa. Percentages are shown to two decimal places, and days to one decimal place. Break-even quantities and reorder levels are rounded up to the next whole unit, because rounding down would leave you short. Economic order quantity is rounded to the nearest whole unit. Interest for a number of days uses a 365-day year. All examples and quiz questions are Hypothetical: they show the method, not real prices or rates.
Unit conversions and per-unit prices
Suppliers quote by the quintal, tonne, case or gross; customers buy by the kilo, litre, pack or piece. Many pricing mistakes are really conversion mistakes. The fix is simple: convert everything to the same unit before comparing or pricing, and work out the price per unit (per kg, per litre, per piece).
If some of what you buy is lost in cleaning, sorting, breakage or drying, spread the full cost over only the usable quantity.
The standard formulas
Common Indian trade units1 kg = 1,000 g1 quintal = 100 kg1 tonne = 1,000 kg = 10 quintals1 litre = 1,000 ml1 dozen = 121 gross = 144 (12 dozen)
Per-unit pricePrice per unit = Total priceQuantity in that unit
Allowing for lossCost per usable unit = Total cost (including freight)Quantity bought × (1 − loss %)
Terms used
Quintal
100 kg. Common for grain, pulses and other farm produce.
Tonne (metric ton)
1,000 kg.
Gross
144 pieces, or 12 dozen.
Per-unit (unit) price
The price for one standard unit, such as per kg or per litre, so packs of different sizes can be compared.
Worked examples
HypotheticalBasicWhich pack is cheaper?
A 500 g pack costs ₹56 and a 1 kg pack costs ₹105.
500 g pack: ₹56 ÷ 0.5 kg = ₹112 per kg
1 kg pack: ₹105 per kg
The 1 kg pack is cheaper by ₹7 per kg.
HypotheticalIntermediateFrom case price to per-pack and per-kg
A case of 24 packs of 200 g costs ₹1,080. A shop sells each pack at ₹50.
Cost per pack = ₹1,080 ÷ 24 = ₹45
Weight per case = 24 × 200 g = 4.8 kg; cost per kg = ₹1,080 ÷ 4.8 = ₹225
Margin per pack = (₹50 − ₹45) ÷ ₹50 = 10.00%
HypotheticalAdvancedQuintal rate to a per-kg selling price, with loss
A trader buys rice at ₹4,200 per quintal plus ₹150 freight per quintal. About 2% is lost in cleaning and handling. He wants a 10% margin.
Cost per quintal delivered = ₹4,350; usable rice = 100 kg × 98% = 98 kg
Cost per usable kg = ₹4,350 ÷ 98 = ₹44.39
Price for a 10% margin = ₹44.39 ÷ 0.90 = ₹49.32 per kg
Pricing from ₹42 per kg alone, without freight and loss, would have given ₹46.67.
Quiz: unit conversions and per-unit prices
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