Paper thickness chart: points, mils & millimeters
A pound rating tells you what a ream weighs. It does not tell you how thick the sheet is — that is a separate measurement, and it is the one you actually mean when you say “thick.” Here are the numbers, with the honest caveat that every one of them moves from mill to mill.
Weight and thickness are two different measurements
80 lb cover typically measures about 0.009 to 0.012 inch — 9 to 12 points, or 0.23 to 0.30 mm — and 100 lb cover typically measures about 0.010 to 0.014 inch, or 10 to 14 points (0.25 to 0.36 mm). 80 lb text is a different paper entirely at roughly 0.005 to 0.007 inch, because a pound number is a weight rating and weight is not thickness.
Those are ranges rather than single numbers on purpose. Thickness is measured directly with a micrometer and called caliper; weight is measured on a scale, one ream at a time, at a parent sheet size you never see. Two sheets can weigh the same and measure differently, which is exactly why the industry quotes cards in points and paper in pounds. If the pound system itself is the confusing part, start with our paper weight guide; this page is about the other axis.
What a point and a mil actually are
One point equals 0.001 inch, one thousandth of an inch. So a 14 pt card is 0.014 inch thick. That is the whole definition.
A mil is the same unit under a different name: one mil is also 0.001 inch, so 14 pt and 14 mil describe an identical sheet. Vinyl and laminate are spoken of in mils, paper in points, but the number does not change when you switch vocabularies. Neither is the typographic point your design software uses for type size — that one is 1/72 inch, an unrelated measurement our print glossary keeps separate.
Metric is one multiplication: points × 0.0254 gives millimeters. So 14 pt is 0.356 mm and 18 pt is 0.457 mm; divide by 0.0254 to go back, and a 0.30 mm sheet lands right around 12 pt.
The paper thickness chart
Read every number below as typical, not specified: caliper varies by mill, by coating, and even by the humidity in the plant, and two sheets sold under the same name can measure a point apart.
| Stock | Points (= mils) | Inches | Millimeters | Where you see it |
|---|---|---|---|---|
| 20 lb bond (copy paper) | ~4 pt | 0.004 in | 0.10 mm | Copiers, forms, letterhead |
| 80 lb text (118 gsm) | 5–7 pt | 0.005–0.007 in | 0.13–0.18 mm | Flyers, brochure panels, inserts |
| 100 lb text (148 gsm) | 6–9 pt | 0.006–0.009 in | 0.15–0.23 mm | Heavier flyers, sell sheets, posters |
| 80 lb cover (216 gsm) | 9–12 pt | 0.009–0.012 in | 0.23–0.30 mm | Light cards, booklet covers, tent cards |
| 100 lb cover (270 gsm) | 10–14 pt | 0.010–0.014 in | 0.25–0.36 mm | Postcards, folders, rack cards |
| 12 pt card | 12 pt | 0.012 in | 0.30 mm | Economy cards, door hangers |
| 14 pt card | 14 pt | 0.014 in | 0.36 mm | The business card default |
| 16 pt card | 16 pt | 0.016 in | 0.41 mm | Premium cards — and the USPS card ceiling |
| 18 pt card | 18 pt | 0.018 in | 0.46 mm | Heavy cards, hang tags, thick menus |
Notice that the point stocks are exact and the pound stocks are ranges. A 14 pt card is defined by its caliper; a 100 lb cover is defined by its weight and lands wherever its bulk puts it. When thickness matters, ask for the mill’s caliper figure and hold a sample.
Why two 100 lb covers measure differently
The answer is bulk: how much thickness a paper gets per unit of weight. Two sheets can carry identical weight and identical gsm and still stack differently, because one spends more of its weight on air and fiber and the other spends it on something dense.
The biggest lever is coating. A gloss or matte coating is mineral — clay and calcium carbonate pressed into a thin, heavy surface layer. It buys sharper ink holdout and a smoother finish, and it buys them with weight. So a coated 100 lb cover generally measures thinner than an uncoated 100 lb cover of the same rating: same pounds on the scale, fewer of them spent on thickness. That is much of where the 10 pt to 14 pt spread in the chart comes from.
Mills engineer for it deliberately, too. High-bulk sheets hit a target caliper at a lower weight, which is how a booklet gets a satisfying spine without a punishing mailing weight, and a felt or linen finish adds measurable caliper before any ink lands on it.
The practical consequence: do not translate between pounds and points and assume you are right. If the piece has to fit an envelope, slot into a holder, or clear a postal minimum, get the caliper for the exact stock and get a sample. Our paper weight converter handles the lb-to-gsm arithmetic; caliper is the part that needs a physical sheet.
What thickness to pick, piece by piece
- Business cards
14 pt is the default and feels professional. 16 pt is noticeably sturdier and is worth it if cards live in toolboxes and back pockets. 12 pt is the economy option; 18 pt and up read as a deliberate statement. Our business card stocks guide goes deeper on coatings, and business cards covers the options.
- Postcards
Thickness is a postal rule here, not a preference — see the next section. Most mailed cards land between 12 and 16 pt, rigid enough to survive automated equipment without leaving the card-price window. See postcards.
- Menus
A reusable menu wants 14 pt or heavier plus a laminate or coating so it wipes down; caliper is what stops it curling after a week of handling. A menu printed fresh daily can drop to text stock. See menus.
- Signs
Different vocabulary entirely. Rigid sign substrates are quoted in millimeters or fractions of an inch — 4 mm corrugated plastic, 3 mm aluminum composite — not in paper points, and the choice is driven by wind and weather rather than feel. See our rigid sign materials guide and rigid signs.
If you would rather answer a few questions than read a chart, our paper picker walks you to a stock based on what the piece has to do.
When thickness is a postal rule, not a preference
For anything going in the mail, caliper stops being a matter of taste. The USPS Domestic Mail Manual sets the card-price physical standards at DMM 101.6.2.2: a card claimed at card prices must be not less than 0.007 inch thick and not more than 0.016 inch thick, alongside height and length limits of 3-1/2 to 4-1/4 inches and 5 to 6 inches. We verified that text at pe.usps.com, but USPS revises the DMM continuously — confirm the current standard at usps.com before you commit a run.
Put that against the chart and two numbers jump out. The 0.007 inch floor is about where 80 lb text tops out, so a card printed on ordinary flyer stock sits right on the minimum. And 0.016 inch is exactly 16 pt — a 16 pt card is at the ceiling and an 18 pt card is over it. A gorgeous 18 pt card is a fine leave-behind and a problem in a mailbox.
Here is why the rule exists, in one sentence: sorting equipment grips and turns mail at speed, so a piece too thin shingles under its neighbor and a piece too thick jams the feed. The same logic drives the rule at DMM 101.1.2: a letter-size piece longer than 6 inches or taller than 4-1/4 inches must be at least 0.009 inch thick or it pays a nonmachinable surcharge.
Our USPS mailer size rules guide maps every dimensional window, and the free mailer size checker tests a specific piece in seconds.
The thickest stock you can actually print
Single-ply cardstock commonly tops out around 18 pt. Past that, thickness comes from lamination rather than from the mill: duplexed stocks glue two sheets together to reach roughly 24 pt, and triplexed stocks add a third — often a colored core that shows as a stripe on the cut edge — to reach 32 pt and beyond. Those are specialty products rather than shelf stock, so availability is worth checking before you design to one.
The real ceiling, though, is the press and the bindery, not the paper. Every device has a maximum caliper it will feed reliably, and many digital presses tap out below what an offset press or a specialty converter will run. Folding is a second limit: heavy stock has to be scored before it will fold without cracking, and past a certain caliper it stops folding cleanly at all.
So the useful version of “what is the heaviest cardstock” is a question about your job, not a number. Tell us what you are printing and ask for samples with the quote — five minutes holding two stocks beats any chart on this page.
Frequently asked questions
- How thick is 80 lb cardstock?
80 lb cover, the stock most people mean by cardstock, typically measures about 0.009 to 0.012 inch, or 9 to 12 points (0.23 to 0.30 mm). 80 lb text is a different paper at roughly 0.005 to 0.007 inch. Caliper varies by mill and coating, so treat those as typical and confirm with a sample.
- Is 14 pt thicker than 100 lb cover?
Usually, but not always. 14 pt is exactly 0.014 inch by definition, while 100 lb cover is a weight rating that typically lands between about 0.010 and 0.014 inch depending on bulk. A coated 100 lb cover generally measures thinner than 14 pt; a bulky uncoated one can measure about the same. Compare calipers, not labels.
- How thick is 100 gsm paper?
Around 0.004 to 0.005 inch, roughly 4 to 5 points or 0.10 to 0.13 mm, a little heavier than copy paper. Gsm measures weight per square meter, not thickness, so caliper still depends on bulk and coating. For reference, 100 gsm is about 68 lb text or about 27 lb bond.
- What is the thickest cardstock you can print on?
Single-ply cardstock commonly tops out near 18 pt, or 0.018 inch. Thicker pieces are duplexed or triplexed, meaning two or three sheets laminated together to reach roughly 24 pt or 32 pt, sometimes with a colored core. The practical limit is the press and bindery, so ask what a given press will run before you design to it.
- How thick should a business card be?
14 pt is the standard and feels professional in hand. Step up to 16 pt if cards get stuffed in pockets and toolboxes, drop to 12 pt when cost per card matters most, and go to 18 pt or a layered stock when the card itself is the impression. Handle samples of your top two before ordering a thousand.
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