paper wight conversion chart

Please use this as a guide for people living in areas where paper is not sold by US Weights.

Introduction

Paper weights and types can be very confusing.
This is a general guide to help understand the sizes and terms and to associate them with items that you are familiar with.

There are two basic systems in use:
* The U.S. system (traditional English system), which sizes the weight in pounds,
* And the Metric system, which sizes the weight in grams / meter squared (g/m²)

The U.S. system is more difficult to understand because the same number in pounds can be used for the thicker card stock or the thinner text papers.
In the U.S. system, a paper's weight is the weight, measured in pounds, of one ream [500 sheets (Courtesy of rvb4life)]. But every type of paper has its own size of ream!

The metric system however is standard across all weights of papers. It measures a fixed size--one square meter.

As a general rule,

* 10-35 gsm is of tissue consistency;
* 35-70 gsm is lighter textweight,
* 70-100 gsm is medium textweight,
* 100-120 gsm is heavy textweight/light cardstock,
* 120-150 gsm is regular cardstock weight,
* 150-200 gsm is heavy cardstock,
* and greater than 200 gsm is super heavy cardstock.

For Pepakura Use, 175-250 gsm is the recommended weight.
Anything lighter will be too flimsy to work with when the Resin goes on.
Anything Heavier will begin to get complicated when making HD folds, but can be used for rigid structural integrity.

Conversion Table:

I take no credit for the information, but researched from reliable sources.
Simplified Table generated by me.
Note: All Values are Averages, Paper Types are Generalised.

Paper Type-------------------------------------------US Weight---------------GSM

Bond/Writing/Ledger (A4/Letter)----------------20 lb-------------------90 gsm

Translucent Vellum Paper (A4/Letter)-----------29 lb-----------------109 gsm

Solid Card Stock (A4/Letter)---------------------110 lb-----------------175 gsm

3" x 5" Index Card--------------------------------110 lb-----------------200 gsm

	-- Bond Ledger	- Offset Text	- Cover -	-- Tag --	- Index -	- Points -	- *Caliper (inches)	-- millimeters --	- Metric (grams/sq meter)
Equivalent	16	40	22	37	33	3.2	.0032	0.081	60.2 gsm
Weight	18	45	24	41	37	3.6	.0036	0.092	67.72 gsm
	20	50	28	46	42	3.8	.0038	0.097	75.2 gsm
	24	60	33	56	50	4.8	.0048	0.12	90.3 gsm
	28	70	39	64	58	5.8	.0058	0.147	105.35 gsm
	29	73	40	62	60	6	.0060	0.152	109.11 gsm
	31	81	45	73	66	6.1	.0061	0.155	116.63 gsm
	35	90	48	80	74	6.2	.0062	0.157	131.68 gsm
	36	90	50	82	75	6.8	.0068	0.173	135.45 gsm
	39	100	54	90	81	7.2	.0072	0.183	146.73 gsm
	40	100	56	93	83	7.3	.0073	0.185	150.5 gsm
	43	110	60	100	90	7.4	.0074	0.188	161.78 gsm
	44	110	61	102	92	7.6	.0076	0.193	165.55 gsm
	47	120	65	108	97	8	.0078	0.198	176.83 gsm
	53	135	74	122	110	9	.0085	0.216	199.41 gsm
	54	137	75	125	113	9	.009	0.229	203.17 gsm
	58	146	80	134	120	9.5	.0092	0.234	218.22 gsm
	65	165	90	150	135	10	.0095	0.241	244.56 gsm
	67	170	93	156	140	10.5	.010	0.25	252.08 gsm
	72	183	100	166	150	11	.011	0.289	270.9 gsm
	76	192	105	175	158	13	.013	0.33	285.95 gsm
	82	208	114	189	170	14	.014	0.356	308.52 gsm
	87	220	120	200	180	15	.015	0.38	312 gsm
	105	267	146	244	220	18	.0175	0.445	385.06 gsm

The darker colored boxes above represent the "most common paper weights" for that category.

Normal paper manufacturing tolerance within a paper production run is + or - 5% to 7% caliper.

via》micro format, inc

** Mesurement Conversion Tool