Paper Weight Calculator - Grammage, Basis Weight, and Ream Weight

A paper weight calculator turns a paper's grammage (gsm) or US basis weight (lb) into the weight of a single sheet and the total weight of any quantity of sheets, in grams, kilograms, pounds, and ounces at the same time.

• • Plan a copy paper order: Estimate the total weight of 5, 10, or 20 reams of 80 gsm A4 copy paper for a delivery or a cart trip.
• • Check a printer spec sheet: Convert a paper's 80 gsm label to its equivalent 60 lb text or 80 lb cover basis weight when the spec sheet uses a different unit.
• • Price invitation or cardstock stock: Calculate the weight of a single 5x7 card on 80 lb cover and the total weight of a 100 card order, then price the job by the kilogram or pound.
• • Convert grammage to basis weight: Translate a metric gsm value into the US basis weight system so international paper orders line up with local warehouse stock.

Paper weight shows up on almost every ream wrapper, office spec sheet, and craft store card. The metric system uses grammage (gsm or g/m²), the mass of one square meter of the paper. The US system uses basis weight, written in pounds and tied to a 500 sheet ream of a stock specific basic sheet size, which is why 20 lb bond, 50 lb text, and 75 gsm paper can weigh about the same.

The page keeps both systems on screen at once. Enter the grammage or basis weight you have, pick the stock type, and the page returns the sheet weight, the total weight, the ream count, and the gsm to lb conversion.

When you need the caliper of the same paper instead of its weight, the paper thickness calculator reads a measured stack and returns the single sheet thickness in pt, mm, and inches.

The calculator runs two simple formulas. In grammage mode it multiplies the paper's area by its grammage to get the sheet weight in grams. In basis weight mode it scales the labelled basis weight by the ratio of the actual sheet area to the stock specific basic sheet area.

• Grammage (gsm): Mass per square meter, the metric system paper weight.
• Basis weight (lb): Pounds per 500 sheet ream at the basic sheet size.
• Stock type: US paper class with its own basic sheet size.
• Sheet length and width (in): Dimensions of the actual paper sheet.
• Quantity (sheets): Number of sheets in the order, pack, or stack.

The page shows grams, kilograms, pounds, and ounces at the same time because ream wrappers, spec sheets, and craft store cards do not agree on one unit.

The basis weight stock type matters. A 20 lb label on bond paper, a 50 lb label on text paper, and a 60 lb label on cover paper do not describe the same density, because each stock has its own basic sheet area (bond 17x22 in, text 25x38 in, cover 20x26 in).

According to NIST Special Publication 811, the inch is defined as exactly 0.0254 metres and the international avoirdupois pound is exactly 453.59237 grams, which is the conversion the page uses for the length, pounds, and ounces outputs.

Once the calculator gives you the total weight of a given sheet count, the paper quantity calculator translates a count of sheets into the printing industry units like quires, reams, bundles, and bales.

Four ideas explain almost every result the paper weight calculator gives: how grammage is defined, how the US basis weight system works, why a basic sheet size matters, and why two papers with the same gsm can still feel different in the hand.

A useful mental model is to treat grammage as the universal spec and basis weight as the legacy US spec. Converting between the two is a one step calculation once the basic sheet area is known, which is why the page shows the equivalent gsm and the equivalent basis weight together.

Notebooks, copy paper, and printer paper are core back to school supplies, so the back to school calculator can put a per student paper budget around the ream count and the price per ream.

Pick the unit you have, choose the stock type, enter the sheet size, and set the quantity. The page updates the sheet, total, and ream outputs as you type.

1. 1 Choose the input mode: Select 'From grammage' for gsm or 'From basis weight' for lb on the wrapper.
2. 2 Enter the weight value: Type the grammage or basis weight. Office copy paper is 70 to 90 gsm or 20 to 24 lb bond.
3. 3 Pick the stock type: Select bond, text, tag, index, bristol, or cover, or pick custom and enter the basic sheet size.
4. 4 Enter the sheet size: Type the length and width in inches. A4 is 11.69 in x 8.27 in, Letter is 11 in x 8.5 in.
5. 5 Set the quantity: Enter the total sheet count. 500 is a ream, 2500 is five reams.
6. 6 Read the results: The page shows the sheet weight in g, kg, lb, and oz, the total weight in kg and lb, the ream count, and the equivalent grammage and basis weight.

A 70 gsm A4 sheet weighs 4.366 g. A 500 sheet ream of 70 gsm A4 paper weighs 2.183 kg, or 4.811 lb. A 2500 sheet order weighs 10.915 kg, or 24.061 lb.

Wedding stationery such as invitations, RSVPs, and place cards usually runs on heavier cover stock, so the wedding budget calculator is the natural place to fold the per card paper cost into the overall stationery line item.

A paper weight check before you order, print, or ship saves paper, ink, courier fees, and printer repairs.

• • Read any paper label: See the same paper in gsm, lb bond, and lb cover at the same time, so you can compare ream wrappers, spec sheets, and craft store cards.
• • Size a copy paper order: Estimate the total weight of a 5, 10, or 20 ream order of A4 or Letter copy paper for a cart trip or delivery.
• • Pick the right cardstock: Calculate the weight of a single 5x7 card on 80 lb cover or 300 gsm cardstock and the total weight of a 100 card order.
• • Plan shipping and postage: Convert a sheet count to kilograms and pounds to estimate shipping weight for a print order or craft kit.

The page is most useful when you treat the result as a working number, not a final answer. Coated, glossy, cotton, and textured papers all shift the weight slightly because the surface treatment changes how much fibre sits in a square meter, and the basic sheet size table assumes a generic office or printing stock.

When the same paper covers a wall instead of sitting in a ream, the wallpaper calculator turns roll length, width, and pattern repeat into a wall coverage estimate.

Real paper does not behave like an ideal square meter of fibre. These factors explain why two papers with the same label can weigh slightly differently.

• • The custom basic sheet size mode trusts the entered length and width without checking that the size matches a real paper stock.
• • The equivalent basis weight output is rounded to the nearest 0.1 lb and the equivalent grammage to the nearest 0.1 gsm, which is fine for ordering but not precise enough for a mill specification.

If you need a mill grade paper weight for a specification or a contract, the page is a planning tool, not a substitute for an ISO 536 lab measurement on a conditioned sample.

According to ISO 536 (Paper and board - Determination of grammage), the grammage of paper and board is determined on a conditioned sample and expressed in grams per square meter, which is the value the page labels as gsm and the unit used to compute the sheet and total weight outputs.

For the caliper side of the same spec, the paper thickness calculator reads a measured stack and returns the single sheet thickness in pt, mm, and inches.