How to Set a Logo's Minimum Size
Most brand guidelines include a minimum size rule. Most of them are also guessed.
Someone picks 25mm because it sounds about right, writes it into the document, and nobody checks. Then the logo goes onto a pen, or a favicon, or the corner of a spreadsheet template, and the counters fill in and the tagline turns to mush.
Minimum size is one of the few numbers in a brand book you can actually determine empirically. It takes about twenty minutes.
What the number actually means
Minimum size is the smallest reproduction at which the logo still reads correctly. Not "is still visible" — reads correctly. The distinction matters, because a logo can be perfectly visible at 8mm while its wordmark has collapsed into a grey smear.
The failure is almost never the icon. Icons are usually chunky enough to survive. What breaks first is:
- Counters — the enclosed spaces in letters like a, e, o, g. When these fill in, the word stops being legible and becomes a shape.
- Thin strokes — hairlines in a wordmark, or a thin rule separating an icon from text.
- Tight negative space — the gap between an icon's elements, which closes up before anything else does.
- The tagline, if you have one. A tagline lockup almost always has a higher minimum than the primary mark, and it's the single most common thing people forget to specify separately.
Find the first of these to fail and you've found your minimum.
Determining it for print
Print is where you need to be most careful, because ink spreads. A stroke that measures 0.3pt in your file will be fatter on paper, and fatter still on uncoated stock or anything absorbent.
The test:
- Place your logo at a range of widths on one artboard — 30mm, 25mm, 20mm, 15mm, 12mm, 10mm, 8mm.
- Label each one with its width.
- Print it on the cheapest, most absorbent paper you have access to. Office copier paper is ideal, because it's worse than anything a real job will use, which gives you margin.
- Look at it at arm's length in normal room light. Not on your monitor. On paper.
The smallest size where the counters are still open and the tagline is still readable is your print minimum. Round up to a round number. If 13mm works and 12mm doesn't, specify 15mm, not 13mm. Nobody wants to measure to the millimetre, and the extra margin absorbs bad printing.
For most wordmark-plus-icon lockups you'll land somewhere between 15mm and 25mm. A standalone icon can usually go to 8-10mm. If your primary lockup can't survive 25mm, that's worth knowing — it may be a sign the mark needs a simplified variant for small use, which is a design decision, not a documentation one.
Determining it for screen
Screens are more forgiving in some ways and less in others. There's no ink spread, but there is pixel snapping, and there's the fact that a lot of your logo's screen usage will be at sizes you don't control.
Same method, different substrate:
- Export the logo as PNG at a range of widths — 200px, 160px, 120px, 100px, 80px, 60px, 40px.
- View them at 100% zoom on a standard-density display, not a Retina one. Your logo will look better on your laptop than on the client's 1080p monitor, and the client's monitor is the real test.
- Check the same failure points: counters, hairlines, negative space.
Most lockups hold up to around 80-120px wide. Icons alone often go to 32px, sometimes 24px if they were designed for it. Below that you're into favicon territory, which genuinely needs its own drawn variant rather than a scaled-down one — at 16px you're placing individual pixels, and no amount of scaling gets you there.
Specify both, and specify the lockup
Two numbers, clearly separated:
- Print minimum — in millimetres, measured on the logo's width (state which dimension you're measuring, because people will assume the wrong one).
- Screen minimum — in pixels, same dimension.
And if you have more than one logo configuration — primary lockup, stacked version, icon alone, with tagline — each one needs its own pair of numbers. They will not be the same. The stacked version usually survives smaller than the horizontal one, because its wordmark gets more width per unit of overall size.
This is the part most guidelines skip, and it's the part that causes the actual problems. Someone reads "minimum size: 20mm", applies it to the tagline lockup, and the tagline is illegible at 20mm because that number was derived from the primary mark.
Document it so it can't be misread
A minimum size page that works usually has:
- The logo at its stated minimum, reproduced at actual size on the page
- A dimension line showing which measurement the number refers to
- The number itself, large enough to read
- The same treatment for each configuration you support
Showing it at actual size matters more than it sounds. A number in a table is abstract. A logo printed at exactly 18mm with "18mm minimum" beside it is something a production person can hold a ruler against.
Put it on the same spread as clearspace. They're the two rules that govern how the logo occupies space, and people look for them together.
A note on the number you inherit
If you're working with an existing brand book that already specifies a minimum, test it before you trust it. It's a five-minute check, and inherited numbers are frequently wrong — either guessed originally, or correct for a logo that has since been redrawn.
If the number turns out to be too small, you're not just correcting a document. You're explaining why a batch of printed material doesn't look right, which is a considerably more useful thing to be able to demonstrate than to assert.
Doing this with GridMe
The testing above is manual by nature — you have to look at the output and make a judgement. No tool can decide for you where legibility fails.
What GridMe's Size Guide stage does handle is the documentation half: laying out the logo at a stepped range of sizes on one sheet, labelled and aligned, so you have something to print for the test and something to hand over afterwards. It builds the ladder, you make the call.
Download GridMe if you'd rather not build that layout by hand every time you set a minimum for a new mark.