Paper Thickness Calculator
Convert paper caliper to total stack height for print runs, packaging, or binder capacity planning.
Tip: Caliper is the thickness of a single sheet. Use manufacturer specs or measure with calipers or a micrometer.
Basis weight reference (lbs per ream) helps correlate caliper with common stocks.
Thickness Overview
Per sheet
0.004 in
(0.102 mm)
Stack height
2 in
(50.8 mm)
How to Use This Calculator
Get the caliper
Use manufacturer data sheets (often in points) or measure a single sheet with calipers. Convert mils to inches by dividing by 1000.
Count sheets or reams
Multiply the caliper by the number of sheets. For reams, use 500 sheets; for booklets or stacks, count actual sheets.
Compare weights
Optionally select a paper type to see typical basis weight and cross-check thickness assumptions.
Formula
Stack Height = Caliper per Sheet * Number of Sheets
Caliper (mil) = Caliper (inch) * 1000
Caliper (mm) = Caliper (inch) * 25.4
Example: Caliper 0.004 in (4 pt) * 500 sheets = 2 inches tall (50.8 mm). That is a typical ream of 20 lb bond paper.
Paper Thickness Essentials
Caliper affects folding, binding, mailing rates, and packaging. Knowing stack height helps verify press settings or mailbox fit.
- Use heavier stock for covers; higher caliper equals a stiffer feel.
- Envelopes and mailers have strict thickness limits (less than 0.25 in for standard letters).
- Stack height impacts storage space for bulk print runs or shipping cartons.
- Prints with varnish or lamination add extra thickness per sheet.
Frequently Asked Questions
What is the difference between caliper and GSM?
Caliper measures thickness, while GSM (grams per square meter) measures weight. Higher GSM often correlates with thicker paper, but coatings can affect thickness.
How accurate are manufacturer caliper specs?
They are averages. Expect small variation between batches. For critical jobs, measure the actual stock delivered.
Can humidity change thickness?
Slightly. Paper absorbs moisture which can swell fibers. Store paper in controlled conditions before printing or binding.
How do I convert points to mils?
In printing, "points" often equals one mil (0.001 in). So 10 pt cover stock is approximately 0.010 in thick.