What Size Stamp Do I Need? A Guide to Trodat & Colop Sizes

Choosing a rubber stamp sounds simple until you’re staring at a list of model numbers like “Printer 20” or “Trodat 4911” and trying to work out whether your six lines of text will actually fit. Order too small and your details end up cramped and hard to read. Order too big and you’re paying for space you’ll never use — and possibly overrunning the edge of a cheque or form.

At Mr Rubber Stamps, we’ve been sizing stamps for Australian businesses for over 20 years, so we know that the right size comes down to three things: how much text or artwork you need, the shape of the impression, and where you’re stamping. Here’s how to get it right.

Start with what goes on the stamp

Before you look at a single model number, jot down exactly what your stamp needs to show. The number of lines and the amount of detail are the biggest factors in choosing a size.

As a rough guide, think in terms of text lines:

• 1–3 lines (a name, an “APPROVED”, a simple return address) suits a small self-inking stamp.
• 4–5 lines (business name, ABN, address, phone) needs a mid-size model.
• 6–7 lines or a logo calls for one of the larger rectangular sizes.
• A logo with text, or fine detail almost always needs more room than people expect — when in doubt, size up.

Keep in mind that smaller stamps mean smaller text. A five-line address squeezed onto a tiny stamp will technically fit, but it may be a strain to read. Legibility matters more than saving a few millimetres.

Trodat self-inking sizes at a glance

Trodat’s Printy range is one of the most popular self-inking families in Australia, and the model numbers correspond to fixed impression sizes. The most common rectangular sizes are:

• Trodat 4910 — approx. 26 x 9 mm: ideal for a single short line, initials or a small signature-style stamp.
• Trodat 4911 — approx. 38 x 14 mm: great for up to 3 lines, such as a name and title.
• Trodat 4912 — approx. 47 x 18 mm: a workhorse for 4–5 lines; one of the most-ordered business sizes.
• Trodat 4913 — approx. 58 x 22 mm: comfortably holds 5–6 lines or text with a small logo.
• Trodat 4915 — approx. 70 x 25 mm: long, wide format that’s perfect for full address blocks.
• Trodat 4926 — approx. 75 x 38 mm: a large square-ish area for logos, detailed artwork or many lines.

If you need a round stamp — common for official marks, seals-style impressions or QC use — Trodat also offers circular models such as the 4630 (about 30 mm diameter) and 4642 (about 42 mm diameter).

Colop self-inking sizes at a glance

Colop’s Printer range is the other major brand we stock, and it maps neatly to similar dimensions, so if you prefer Colop you won’t miss out on any size:

• Colop Printer 10 — approx. 27 x 10 mm: one line, compact and tidy.
• Colop Printer 20 — approx. 38 x 14 mm: up to 3 lines.
• Colop Printer 30 — approx. 47 x 18 mm: 4–5 lines; a reliable everyday business size.
• Colop Printer 40 — approx. 59 x 23 mm: 5–6 lines or text plus a small graphic.
• Colop Printer 50 — approx. 69 x 30 mm: large area for detailed address blocks or logos.
• Colop Printer 60 — approx. 76 x 37 mm: the big one, for logos with plenty of accompanying text.

Colop also offers round options (such as the R30 and R40) for circular designs.

Both brands deliver crisp, consistent impressions, so the choice between Trodat and Colop often comes down to feel, availability and price. If you’d like help deciding, our comparison of the two brands walks through it in detail: Colop vs Trodat: How to Pick the Right Self-Inking Stamp for You.

Match the size to the job

The right dimensions also depend on where the stamp will land:

Documents and letterhead. For invoices, letters and forms, a mid-size rectangular stamp (Trodat 4912 / Colop Printer 30 and up) gives you room for your business details without dominating the page.

Cheques and small forms. Space is tight, so a smaller model like the Trodat 4911 or Colop Printer 20 keeps your mark neat and inside the lines.

Logos and branding. Artwork needs breathing room. Reach for a larger square-format stamp such as the Trodat 4926 or Colop Printer 60 so fine lines don’t clog or blur.

Date stamps. If you need a changeable date, our date stamps come in their own sizes, and you can add a line or two of custom text above or below the date band.

Heavy, repeated use. For warehouses, dispatch and high-volume stamping, a robust heavy duty or commercial stamp is built to keep going.

A few quick tips before you order

Measure the space where the stamp will actually be used, then choose a model that fits comfortably with a little margin. Count your lines and remember that logos and fine detail need more area than plain text. And if your text sits between two sizes, it’s almost always better to go up — a slightly larger stamp is far easier to read than one that’s crammed.

Still not sure? We’ll size it for you

The quickest way to get it right is to let us check your artwork before we manufacture. Send us your text and any logo and we’ll recommend the ideal Trodat or Colop size, free of charge.

Browse our full range of self-inking stamps or request a free quote today — and if you order and approve by 2:30 PM, we’ll manufacture and ship your custom stamp the same day.