Paper Weight Calculator — GSM to Grams & Kilograms
Find the exact weight of a stack or ream of paper. Enter the GSM rating from the packaging, choose a standard size (A4, A3, Letter, Legal…) or set custom dimensions, specify the sheet count, and get the per-sheet and total weight instantly.
g/m²
Paper size
Weight of the full stack of sheets
2,494.8 g
totalPaper fibre (per sheet)
0.2%
Remaining stack
99.8%
- 1
Sheet area (m²)
210 × 297 ÷ 1,000,000 = 0.06237Width × height in mm converted to square metres. - 2
Weight per sheet (g)
80 × 0.06237 = 4.9896 - 3
Total weight (kg)
4.9896 × 500 ÷ 1,000 = 2.495
How does this calculator work?
Paper weight (g per sheet) = GSM × sheet area (m²). A 210 × 297 mm A4 sheet at 80 gsm weighs about 5 g; 500 sheets weigh ~2.5 kg. Enter GSM, paper size and sheet count to get total weight in grams, kilograms and pounds — useful for print-run costing, postage estimation and freight planning.
Formula
How this is calculated
GSM stands for grams per square metre — the international standard for paper weight. It tells you how many grams one square metre of that paper weighs. To find the weight of a single sheet, multiply the GSM by the sheet's area in square metres. For a 210 × 297 mm A4 sheet at 80 gsm: area = 0.210 × 0.297 = 0.06237 m², weight = 80 × 0.06237 = 4.99 g per sheet. A ream of 500 sheets therefore weighs 500 × 4.99 ≈ 2.50 kg — which matches the weight printed on most A4 ream packaging.
Knowing paper weight matters when shipping printed materials (a box of 5,000 flyers has a real weight you need for freight quotes), when choosing paper for double-sided printing (heavier paper resists show-through), or when estimating postage for booklets and catalogues. GSM is directly comparable across all paper sizes — a 160 gsm A5 card weighs the same per square metre as a 160 gsm A3 poster.
This calculator converts GSM to grams and kilograms for any quantity and also shows pounds for US users. The formula is exact; real-world weights may differ by ±1–2% from moisture content, manufacturing tolerances and coating.
Frequently asked questions
Standard office copy paper is 75–80 gsm. Premium copy paper is 90–100 gsm. Inkjet photo paper is typically 120–180 gsm; glossy photo paper 200–260 gsm. Business cards range from 300 to 450 gsm, and thick card or cover stock starts at 160 gsm.
A ream of 500 sheets of A4 80 gsm paper weighs 500 × (80 × 0.210 × 0.297) ≈ 2,495 g ≈ 2.50 kg. Most office paper packaging confirms this: a standard ream of 80 gsm A4 weighs roughly 2.5 kg.
GSM (grams per square metre) is the metric system used internationally. US basis weight expresses the weight in pounds of a ream of 500 sheets at a "basic size" that varies by paper type — 17 × 22 in for bond paper, 25 × 38 in for book paper. A 20 lb bond paper is approximately 75 gsm; 24 lb bond is approximately 90 gsm. GSM is unambiguous and directly comparable across paper types.
Also known as
TG we-Calculate Editorial Team. (2026). Paper Weight Calculator — GSM to Grams & Kilograms [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/paper-weight-calculator
TG we-Calculate Editorial Team. "Paper Weight Calculator — GSM to Grams & Kilograms." TG we-Calculate. 2026. https://we-calculate.com/calculator/paper-weight-calculator.
TG we-Calculate Editorial Team, "Paper Weight Calculator — GSM to Grams & Kilograms," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/paper-weight-calculator
@misc{wecalculate_paper_weight_calculator, title = {Paper Weight Calculator — GSM to Grams & Kilograms}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/paper-weight-calculator}}, year = {2026}, note = {TG we-Calculate} }
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