Paperboard Professional Toolkit
Unit Conversions
All the conversions paperboard professionals need — pricing, basis weight, caliper, stiffness, and more.
Pricing & Currency
EUR/USD Exchange Rate
Set your exchange rate for all currency conversions below
Short Ton ↔ Metric Ton
USD pricing conversion (1 short ton = 0.907185 metric ton)
USD / Short Ton
⇄
USD / Metric Ton
USD / Metric Ton
⇄
USD / Short Ton
1 short ton = 2,000 lbs = 907.185 kg | $/ST × (1/0.907185) = $/MT
Full Pricing Matrix
Enter any one price — all four update automatically
USD / Short Ton
USD / Metric Ton
EUR / Short Ton
EUR / Metric Ton
USD input is editable — EUR outputs use the rate set above
$/CWT ↔ $/Short Ton & $/MT
Hundredweight pricing (common in North American markets)
USD / CWT
→
USD / Short Ton
→
USD / Metric Ton
CWT = per hundredweight (100 lbs) | $/CWT × 20 = $/ST
Basis Weight
GSM ↔ lbs / 3,000 ft²
SBS/CUK paperboard standard basis weight
GSM (g/m²)
⇄
lbs / 3,000 ft²
lbs / 3,000 ft²
⇄
GSM (g/m²)
GSM × 0.6120 = lbs/3000ft² | lbs/3000ft² ÷ 0.6120 = GSM
GSM ↔ lbs / 1,000 ft²
Folding boxboard & liner alternative basis
GSM (g/m²)
⇄
lbs / 1,000 ft²
lbs / 1,000 ft²
⇄
GSM (g/m²)
GSM × 0.2040 = lbs/1000ft² | 1000 ft² = 92.90 m²
M Weight Calculator
Weight of 1,000 sheets of a given size and basis weight
Sheet Width (in)
Sheet Length (in)
Basis Weight (lbs / 3,000 ft²)
M Weight (lbs)
—
M Weight (kg)
—
Sheet Area
—
M Wt = (W × L × BW) / 3,000 | W and L in inches
Caliper
Points / Mils / Microns / mm
Enter any unit — all others update instantly (1 pt = 1 mil = 0.001 inch)
Points (pt)
Mils (thou)
Microns (μm)
Millimeters (mm)
1 pt = 1 mil = 0.001 in = 25.4 μm = 0.0254 mm
Taber Stiffness
gf·cm ↔ mN·m
Taber stiffness unit conversion
gf·cm
⇄
mN·m
mN·m
⇄
gf·cm
1 gf·cm = 0.09807 mN·m | 1 mN·m = 10.197 gf·cm
Geometric Mean Stiffness
√(MD × CD) — used in grade matching
Taber MD (gf·cm)
Taber CD (gf·cm)
Geo Mean (gf·cm)
—
Geo Mean (mN·m)
—
MD/CD Ratio
—
MD/CD ratio <2.5 generally preferred for carton performance
Printing & Pressroom
Ink Consumption Estimator
Approximate ink usage for offset printing
Sheets (000s)
Coverage %
Sheet Size (in²)
Colors (#)
Ink (lbs)
—
Ink (kg)
—
~1.5 lbs ink per 1,000 ft² at 100% coverage (offset, coated board)
Board Yield Calculator
Sheets per short ton / metric ton
Sheet Width (in)
Sheet Length (in)
Basis Weight (lbs / 3,000 ft²)
Sheets / Short Ton
—
Sheets / MT
—
lbs / Sheet
—
Imperial: sheet wt (lbs) = (W×L×BW)/(3000×144)
Reel Calculators
Reel Diameter from Length
Calculate outer diameter given reel length and thickness
Reel Length (m)
Thickness (µm)
Core ID (mm)
Core Wall (mm)
Outer Diameter (mm)
—
D = √((4 × L × t / π) + core_OD²) | core_OD = core_ID + 2×wall
*Default core wall: 10 mm / 0.4 inch
*Default core wall: 10 mm / 0.4 inch
Reel Length from Dimension
Calculate reel length from outer and core diameters
Thickness (µm)
Outer Diameter (mm)
Core ID (mm)
Core Wall (mm)
Reel Length (m)
—
L = π × (D² − core_OD²) / (4 × t) | *Default core wall: 10 mm
Reel Length from Weight
Board weight only — exclude core, plugs, etc.
Net Weight (kg)
Width (mm)
GSM (g/m²)
Reel Length (m)
—
L = weight_kg × 1,000,000 / (width_mm × GSM)
Reel Weight from Dimension
Board weight only — exclude core, plugs, etc.
GSM (g/m²)
Thickness (µm)
Width (mm)
Outer Diameter (mm)
Core ID (mm)
Core Wall (mm)
Net Weight (kg)
—
W = π × GSM × width × (D² − core_OD²) / (4,000,000 × t_µm) | *Default core wall: 10 mm
Reel Weight after Diameter Reduction
New weight when reel is reduced to a smaller diameter
Original Weight (kg)
Original Diameter (mm)
Core ID (mm)
Core Wall (mm)
New Diameter (mm)
New Weight (kg)
—
new_wt = orig_wt × (D_new² − core_OD²) / (D_orig² − core_OD²)
Pallet & Price Calculators
Pallet Weight Calculator
Total board weight for a given number of sheets
Number of Sheets
Sheet Width (mm)
Sheet Length (mm)
GSM (g/m²)
Weight (kg)
—
Weight (lbs)
—
weight_kg = sheets × (W_mm/1000) × (L_mm/1000) × GSM / 1000
Price Calculator
Convert between price per 1,000 sheets and price per tonne
Price/1,000 sheets → Price/tonne
Price per 1,000 Sheets
Weight per 1,000 Sheets (kg)
Price / Tonne
—
Price/tonne → Price/1,000 sheets
Price per Tonne
Weight per 1,000 Sheets (kg)
Price / 1,000 Sheets
—
price/tonne = price/1k × 1000 / wt_1k | price/1k = price/tonne × wt_1k / 1000
Yield Calculator
Area yield gain when switching to a lighter grammage
Current GSM (g/m²)
New GSM (g/m²)
Yield Gain (%)
—
More sheets / tonne
—
yield % = (old_gsm / new_gsm) × 100 | e.g. 310 → 295 gsm = 5.1% more sheets per tonne
Quick Reference
Key Conversion Factors
Paperboard industry constants at a glance
| From | To | Factor | Notes |
|---|---|---|---|
| Short tons | Metric tons | × 0.907185 | 1 ST = 2,000 lbs |
| Metric tons | Short tons | × 1.10231 | 1 MT = 2,204.6 lbs |
| GSM | lbs/3000ft² | × 0.6120 | SBS basis weight |
| lbs/3000ft² | GSM | × 1.6340 | SBS basis weight |
| GSM | lbs/1000ft² | × 0.2040 | Alt basis weight |
| Points (pt) | Microns | × 25.4 | 1 pt = 1 mil = 0.001" |
| Microns | Points | × 0.03937 | |
| gf·cm | mN·m | × 0.09807 | Taber stiffness |
| mN·m | gf·cm | × 10.197 | Taber stiffness |
| $/Short Ton | $/Metric Ton | × 1.10231 | Pricing conversion |
| $/CWT | $/Short Ton | × 20 | 100 lbs × 20 = 2,000 lbs |
| inches | mm | × 25.4 | |
| mm | inches | × 0.03937 | |
| lbs | kg | × 0.453592 | |
| kg | lbs | × 2.20462 |