Stamp Size Guide: Common Sizes in mm, Inches and Pixels

Updated 28 September 2026

How big should a stamp be? Here are the sizes stamp shops sell most often, and how to convert them to pixels so your digital stamp prints sharply.

Diameter	Inches	Typical use
30 mm	1.2 in	Small date or initial stamps
40 mm	1.6 in	The most common round company stamp
45 mm	1.8 in	Round stamps with a logo in the middle
50 mm	2.0 in	Seals and certificates

Size	Lines of text	Typical use
38 × 14 mm	3	Short marks: PAID, COPY, RECEIVED
47 × 18 mm	4	Name and address stamps
58 × 22 mm	5	Full company address with phone and email
70 × 30 mm	6–7	Company details with VAT or registration number

Exact sizes differ slightly between manufacturers, so check the product page of the shop you order from.

For printing, the rule of thumb is 300 pixels per inch (ppi). To convert millimetres to pixels:

pixels = millimetres ÷ 25.4 × 300

A 40 mm stamp needs about 472 px.
A 50 mm stamp needs about 591 px.
The PNG from our stamp maker is 500 × 500 px — enough for a sharp stamp up to about 42 mm (1.7 in) when printed.

On screen and in PDFs that are only viewed, not printed, 500 px is more than enough at any normal size.

Look at where it goes. Measure the empty space on your invoice or form; the stamp should fit without covering text.
Count your lines. Each line of text needs roughly 3.5–4 mm of height to stay readable.
Logos need room. Round stamps with a logo work best at 45 mm or larger.

What is the standard size of a company stamp?

Round company stamps are most often 40 mm across. Rectangular address stamps are most often around 47 × 18 mm or 58 × 22 mm.

Is the downloaded stamp big enough to print?

Yes, up to about 42 mm (1.7 in) at print quality (300 ppi). For larger printed stamps, have a stamp shop recreate the design as vector artwork.

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Put a stamp image in a Word document: insert it in front of text, keep the transparent background, repeat it on every page with the header, and export to PDF.
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What belongs on a company stamp — name, legal form, address, contact details, registration or VAT number — with layout examples and when a stamp has legal weight.