METRIC CONVERSION - PAPER WEIGHT

Outside of North America most of the world uses metric basis weights for paper expressed as grams per square meter - gsm or gm2. One advantage of metric measurement is that the basis weight of paper is an absolute value and is not affected by the type of paper. The charts below show the equivalent metric basis weights for each type of paper.

 

Basis
Weight
Pounds
Grams Per
Square Meter
(GSM)
Basis
Weight
Pounds
Grams Per
Square Meter (GSM)
Basis
Weight
  Pounds 

Grams Per
Square Meter
(GSM)
WRITING
BASIS SIZE 17X22 (FACTOR =3.760)
BOOK, OFFSET
BASIS SIZE 25X38
(FACTOR =1.480)
PRINTING, BRISTOL
BASIS SIZE 22.5X28.5
(FACTOR = 2.193)
13
49
45
67
67
147
15
56
50
74
80
175
16
60
60
89
90
197
17
64
70
104
100
219
20
75
80
118
120
263
24
90
100
148
140
307
28
105
120
178
160
351
32
120
 
 
 
 
80
395
36
135
200
438
 
  
NEWS, TAG
BASIS SIZE24X36
(FACTOR = 1.627)
COVER
BASIS SIZE 20X26
(FACTOR = 2.704)
INDEX, BRISTOL
BASIS SIZE 25.5X30.5
(FACTOR = 1.808)
100
163
50
135
90
163
125
204
60
162
110
199
150
244
65
176
140
253
175
285
80
216
  
200
326
90
243
 
100
270

BASIC WEIGHTS AND GRAMS PER SQUARE METER

CONVERSION FACTORS FROM LBS./500 SHEETS TO GRAMS/METER²

GRADE
BASIS
SIZE
CONVERSION
FACTOR
Writing
17 x22
3.760
Book
25 x 38
1.480
Cover
20 x 26
2.704
Index
25.5 x 30.5
1.808
Bristol
22.5 x 28.5
2.193
News
24 x 36
1.627

Example: 50# Offset (25x38) x 1.480 = 74.0 g/m²

METRIC CONVERSION
PAPER WEIGHT CONVERSION

g/m²
Basis
Wt/M
Grade
g/m²
Basis
Wt/M
Grade
34
17 x 22
18 M
9 lb. Manifold
148
25 x 38
200 M
100 lb. Book
38
17 x 22
20M
10 lb. Manifold
150
17 x 22
80 M
40 lb. Ledger
44
25 x 38
60 M
30 lb. Book
159
24 x 37
200 M
100 lb. Tag
45
17 x 22
24 M
12 lb. Register
163
25.5 x 30.5
180 M
Index Bristol
49
17 x 22
26 M
13 lb. Register
175
20 x 26
130 M
65 lb. Cover
52
25 x 38
70 M
35 lb. Book
178
25 x 38
240 M
120 lb. Book
57
17 x 22
30 M
15 lb. Register
182
22.5 x 28.5
166 M
Stationary Bristol
59
25 x 38
80 M
40 lb. Book
197
24 x 37
250 M
125 lb. Tag
60
17 x 22
32 M
16 lb. Bond
198
22.5 x 28.5
180 M
Printing Bristol
67
25 x 38
90 M
45 lb. Book
199
25.5 x 30.5
220 M
Index Bristol
68
17 x 22
36 M
18 lb. Duplic.
207
25 x 38
280 M
Book, Cover Wh.
74
25 x 38
100 M
50 lb. Book
219
22.5 x 28.5
200 M
Vellum Bristol
75
17 x 22
40M
20 lb. Bond
238
24 x 37
300 M
 Tag150 lb.
81
25 x 38
110 M
55 lb. Book
242
20 x 26
180 M
Cover Bristol
89
25 x 38
12M0
60 lb. Book
243
22.5 x 28.5
220 M
Printing Bristol
90
17 x 22
48 M
24 lb. Bond
252
22.5 x 28.5
230 M
Printing Bristol
104
25 x 38
140 M
70 lb. Book
253
22.5 x 30.5
280 M
Index Bristol
105
17 x 22
56 M
28 lb. Ledger
263
22.5 x 28.5
240 M
Stationary Bristol
119
25 x 38
160 M
80 lb. Book
278
24 x 37
350 M
175 lb. Tag
120
17 x 22
64 M
32 lb. Ledger
306
22.5 x 28.5
280 M
Printing Bristol
125
22.5 x 28.5
114 M
Vellum Bristol
307
25.5 x 30.5
340 M
Index Bristol
133
25 x 38
180 M
90 lb. Book
318
24 x 37
400 M
200 lb. Tag
135
17 x 22
72 M
36 lb. Ledger
350
22.5 x 28.5
320 M
Printing Bristol
136
20 x 26
100 M
Cover
352
20 x 26
260 M
Dbl. Thick Cover
137
22.5 x 28.5
125 M
Vellum Bristol
439
22.5 x 28.5
400 M
Stationary Bristol
147
22.5 x 28.5
134 M
Vellum Bristol
486
20 x 26
360 M
Dbl. Thick Bristol
Equivalents are accurate within 2 grams

PAPER SIZE CONVERSION

I.S.O. Sizes "A"
Metric size
 
A-1 23.5 x 33
59.4 cm. x 84.1 cm.
A-2 16.5 x 23.5
42.0 cm. x 59.4 cm.
A-3 11.75 x 16.5
29.7 cm. x 42.0 cm.
A-4 8.25 x 11 11/16
21.0 cm. x 29.7 cm
A-5 5 7/8 x 8.25
14.8 cm. x 21.0 cm.
A-6 4 1/8 x 5 7/8
10.5 cm. x 14.8 cm.
A-7 2 7/8 x 4 1/8
7.4 cm. x 10.5 cm.
 










   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
     

 

>