Paper M-Weight Calculator [proxy]

M-weight refers to the weight of 1,000 sheets of paper. Use this calculator to easily measure m-weight by providing the sheet size, basis weight, and basic size of the paper (see the example below). When filling in these fields, use decimal fractions where necessary; and give all lengths in inches and weight in pounds.

M-WEIGHT CALCULATOR
Given Sheet Size:	× (length × width)
Basis Weight:	lbs.
Select... (Or type in values below.)
Basic Size:	× (height × width)

M-Weight =	lbs.

Disclaimer:

The numerical results from this calculator are estimates only and are not guaranteed.

Be aware that individual mills may use slightly different methods of calculating m-weight. Also, certain products — particularly higher-caliper SBS and Recycled Board — can vary dramatically in basis weight (and therefore m-weight).

Lastly, actual selling m-weight may be calculated on the full width of the roll (i.e., your size plus waste), thereby increasing the m-weight amount. Please call your sales representative to confirm m-weight.

Example

Find the m-weight for a sheet of 11″ × 17″ Book paper with a basis weight of 70 lbs.

Formula:

(Area of Given Sheet) × Basis Weight

Area of Basic Size

Rounded Ream Weight × 2

M-Weight

Equation:

(11 × 17) × 70

(25 × 38)

13.78 × 2

27.56

Note that in this example, the area of the given sheet size is 11 × 17 = 187 inches², or less than 336 inches²; which means, according to the m-weight rounding rules (see below), that the ream weight should be rounded to the nearest hundredth of a pound.

Specifications

Rounding Rules:

Sheet Size	Ream Weights
864 inches² or larger.	Ream Weight calculated to nearest pound, e.g.: 148 lbs.
336 inches² to 864 inches²	Ream Weight calculated to nearest half pound, e.g.: 148.5 lbs.
Less than 336 inches²	Ream Weight calculated to nearest one hundredth of a pound, e.g.: 148.57 lbs.

Terms & Definitions

Ream:: 500 sheets of paper cut to a given standard size for a particular grade.
Ream Weight:: The weight of 500 sheets of paper.
M-weight:: The weight of 1,000 sheets of paper (or two reams).
Basis Weight:: The weight of a ream, measured in pounds. (See supplemental tables below.)
Basic Size:: The standard sheet size from which the basis weight of a given grade of paper is determined.

Supplemental Tables of Approximate Basis Weights

For C1S and C2S SBS

	C1S SBS	C2S SBS
7 pt	105	115
8 pt	110	125
9 pt	120	135
10 pt	130	145
12 pt	150	172
14 pt	162	185
15 pt	171	190
16 pt	180	204
18 pt	198	220
20 pt	216	240
22 pt	234	260
24 pt	250	275

For Recycled Paperboard
(Clay News, Clay Kraft, Clay White, Chipboard)

Caliper (inches)	Basis Weight (lbs.)
.040	160
.038	152
.036	144
.034	136
.032	128
.030	120
.028	112
.026	104
.024	96
.022	88
.020	82
.018	77
.016	69
.015	65
.014	63
.013	60
.012	56

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M-weight is the weight of 1,000 sheets (that is, two standard 500-sheet reams) of paper, measured in pounds. On the label of a paper ream, the m-weight is often given after the dimensions of the paper in the ream —
for example,
17″ x 22″—47M.
The capital letter ‘M’, like the Roman numeral M, designates the number 1,000; the ‘47’ indicates that 1,000 sheets of this paper weigh a total of 47 lbs.

Paper M-Weight Calculator