Formula used
| Calculation | Formula |
|---|---|
| Single-sheet thickness | Stack height ÷ number of sheets |
| Stack height | Adjusted sheet thickness × number of sheets |
| Sheet count | Stack height ÷ adjusted sheet thickness |
| GSM estimate using density | Thickness in µm = GSM ÷ density in g/cm³ |
| GSM estimate using bulk | Thickness in µm = GSM × bulk in cm³/g |
| Paper bulk | Thickness in µm ÷ GSM |
| Spine width | Book block + covers + binding allowance |
| Folded layers | Layers = 2folds |
How to use this calculator
Choose the calculation mode that matches your known measurements. Enter values with their correct units. Review the result and its displayed working steps carefully.
Measure a tall stack when individual sheets are difficult. Use firm contact without crushing the paper fibres. Repeat measurements and average them for more reliable results.
Select pages when calculating a printed book or booklet. Choose one-sided or two-sided printing before calculating sheets. Add cover layers and binding allowance for production planning.
Example data
| Example | Known values | Expected result |
|---|---|---|
| Measured stack | 10 mm and 100 sheets | 100 µm per sheet |
| Copier paper stack | 100 µm and 500 sheets | 50 mm stack |
| GSM estimate | 80 GSM and 0.80 g/cm³ | About 100 µm |
| Bulk calculation | 120 µm and 100 GSM | 1.20 cm³/g |
| Double-sided book | 200 pages and 100 µm sheets | 100 sheets before covers |
Common paper thickness reference
Reference values are useful for early estimates only. Manufacturers can produce different calipers at identical paper weights. Always use supplier data for final printing decisions.
| Material | Typical GSM | Typical thickness | Typical use |
|---|---|---|---|
| Newsprint | 45 g/m² | 70 µm | Newspapers and inserts |
| Copier paper | 80 g/m² | 100 µm | Office printing |
| Bond paper | 80 g/m² | 105 µm | Letters and forms |
| Offset paper | 80 g/m² | 110 µm | Books and commercial print |
| Coated paper | 100 g/m² | 90 µm | Brochures and magazines |
| Gloss paper | 130 g/m² | 120 µm | Photographic marketing print |
| Matte paper | 130 g/m² | 135 µm | Premium readable print |
| Cardstock | 216 g/m² | 250 µm | Cards and dividers |
| Cover stock | 250 g/m² | 300 µm | Book covers |
| Kraft paper | 120 g/m² | 160 µm | Packaging and wrapping |
| Tissue paper | 18 g/m² | 35 µm | Wrapping and craft work |
| Photo paper | 200 g/m² | 220 µm | Inkjet photographs |
| Label stock | 150 g/m² | 170 µm | Labels and stickers |
| Corrugated board | 600 g/m² | 4,000 µm | Boxes and protective packaging |
Pages, sheets, GSM, caliper, and bulk
A page is one printable side of a sheet. A leaf and a sheet usually mean one piece. Double-sided printing places two pages on each sheet.
GSM measures mass per square metre, not thickness. Caliper measures the physical thickness of one sheet. Paper formulation changes thickness at the same paper weight.
Bulk compares thickness with paper weight using a ratio. Higher bulk usually means a thicker sheet per GSM. Coating and calendering can lower the measured paper bulk.
Frequently asked questions
1. What is paper caliper?
Paper caliper is the thickness of one paper sheet. It is commonly measured in micrometres, mils, or points. Supplier specifications remain best for precise production work.
2. Can GSM determine exact paper thickness?
No, GSM measures weight rather than exact sheet thickness. Density, fibres, coating, and compression affect the final caliper. Use GSM calculations only as informed thickness estimates.
3. Why measure a stack instead of one sheet?
One sheet can be too thin for common rulers. A larger stack reduces the relative measurement error. Divide the stack height by its sheet count.
4. How many pages are on one sheet?
One sheet has two printable sides called pages. Single-sided printing uses only one available page side. Double-sided printing normally uses both page sides fully.
5. What is paper bulk?
Paper bulk is thickness divided by paper grammage. It is commonly expressed as cubic centimetres per gram. Higher values indicate greater thickness for equal GSM.
6. Does compression change stack height?
Yes, pressure can temporarily reduce a paper stack. Binding processes can also compress fibres and trapped air. Enter a compression percentage for practical planning adjustments.
7. Does moisture affect paper thickness?
Paper fibres can expand when they absorb moisture. Storage conditions therefore influence caliper and stack height. Use conditioned samples for the most repeatable measurements.
8. How is book spine width estimated?
Convert printed pages into the required sheet count. Multiply sheets by adjusted caliper, then add covers. Include a binding allowance from your chosen printer.
9. Are preset paper values guaranteed?
No, presets provide representative starting values for planning. Real paper varies by brand, finish, and manufacture. Replace presets with measured or supplier-provided caliper data.