Paper Weight Calculator
Calculate paper weight in grams, pounds, and convert between GSM and basis weight measurements
Paper Specifications
Paper Dimensions
Quantity
How Paper Weight Works
Paper weight is measured in two primary systems: GSM (Grams per Square Metre) and Basis Weight (measured in pounds). Both systems help determine the thickness, quality, and suitability of paper for different applications.
GSM Measurement
GSM represents the weight of one square metre of paper in grams. This is the international standard and provides a direct measurement of paper density. Higher GSM values indicate thicker, heavier paper that typically offers better durability and print quality.
Weight (grams) = Length (metres) × Width (metres) × GSM
Common Paper Types by GSM
| Paper Type | GSM Range | Common Applications |
|---|---|---|
| Copy Paper | 70-90 GSM | Office printing, letters, documents |
| Premium Copy Paper | 90-120 GSM | Professional documents, presentations |
| Light Cardstock | 130-200 GSM | Flyers, brochures, light covers |
| Photo Paper | 180-300 GSM | Professional photography, glossy prints |
| Heavy Cardstock | 250-400 GSM | Business cards, invitations, packaging |
Basis Weight System
Basis weight measures the weight of 500 sheets (one ream) of paper cut to specific basic sizes. Different paper types have different basic sizes, making direct comparison challenging without conversion to GSM.
| Paper Type | Basic Size (inches) | Common Basis Weights |
|---|---|---|
| Bond Paper | 17″ × 22″ | 16, 20, 24, 28 lbs |
| Text Paper | 25″ × 38″ | 60, 70, 80, 100 lbs |
| Cover Paper | 20″ × 26″ | 80, 100, 120 lbs |
| Index Paper | 25.5″ × 30.5″ | 90, 110, 140 lbs |
Paper Size Standards
The UK follows the ISO 216 standard for paper sizes, commonly known as the A-series. Each size is exactly half the area of the next larger size, making scaling and folding straightforward.
Standard UK Paper Sizes
| Size | Millimetres | Inches | Common Uses |
|---|---|---|---|
| A0 | 841 × 1189 mm | 33.1″ × 46.8″ | Large posters, technical drawings |
| A1 | 594 × 841 mm | 23.4″ × 33.1″ | Flip charts, large posters |
| A2 | 420 × 594 mm | 16.5″ × 23.4″ | Small posters, architectural plans |
| A3 | 297 × 420 mm | 11.7″ × 16.5″ | Tabloid newspapers, large documents |
| A4 | 210 × 297 mm | 8.3″ × 11.7″ | Letters, documents, magazines |
| A5 | 148 × 210 mm | 5.8″ × 8.3″ | Notebooks, small brochures |
| A6 | 105 × 148 mm | 4.1″ × 5.8″ | Postcards, small flyers |
Frequently Asked Questions
What’s the difference between GSM and basis weight?
GSM measures weight per square metre in grams, providing a universal standard. Basis weight measures the weight of 500 sheets at specific basic sizes in pounds. GSM is more straightforward for comparison across different paper types.
How do I choose the right paper weight for my project?
Consider your application: 70-90 GSM for everyday printing, 120-160 GSM for professional documents and light brochures, 200-300 GSM for photo printing and premium materials, and 300+ GSM for business cards and packaging.
Does higher GSM always mean better quality?
Not necessarily. Higher GSM indicates thicker, more durable paper, but the best choice depends on your specific needs. Heavier paper may jam in some printers and costs more, whilst lighter paper may be perfectly adequate for many applications.
Can I use this calculator for cardboard and thick materials?
Yes, the calculator works for any paper-based material. However, very thick materials (over 500 GSM) may require different handling considerations for printing and processing.
Why do my calculation results differ slightly from package specifications?
Small variations can occur due to manufacturing tolerances, moisture content, and measurement precision. Our calculator provides theoretical weights based on perfect conditions and exact dimensions.
How accurate is the weight calculation?
The calculator provides theoretical weights with high precision. Actual weights may vary by ±2-5% due to manufacturing tolerances, humidity, and material composition variations.