Logo Testing Checklist: Favicon Size, One Color, Contrast and Trademark Basics

A logo that looks great on a large artboard can fail in the places it will actually be used: a browser tab, a dark-mode app, an embroidered shirt, a faxed invoice. Testing catches these problems while they are still cheap to fix.

This checklist works for any logo, but it is written with monograms and lettermarks in mind, since letter-based marks have specific failure points. Work through it in order; the early tests eliminate the most designs.

1. Small-size tests

Small sizes are where most logos fail, so start here.

• 16 × 16 pixels. The classic favicon size in browser tabs. Can you still tell what it is?
• 32 × 32 pixels. Common favicon and toolbar size. Are the letters identifiable?
• 48 to 64 pixels. Typical avatar size in comment threads and chat apps.
• Printed at about 1 cm (0.4 in) wide. Roughly the size on a pen, a label, or the corner of a document.

What to look for:

• Hairlines disappearing. Thin serifs and strokes vanish first.
• Counters filling in. The holes in letters like A, B, e and o close up.
• Gaps merging. In interlocking monograms, small gaps between overlapping letters blur into solid shapes.
• Frames competing with letters. A detailed ring or wreath can overpower tiny initials.

If the main logo fails at 16 pixels, that is normal for detailed marks. The fix is a simplified small-size version, such as dropping the frame, thickening strokes or using a single initial, rather than abandoning the design.

2. Single-color test

Convert the logo to one flat color with no gradients, shadows or tints.

• Black on white. Does it still work? Is anything lost?
• White on black (reversed). Does it still read? Thin strokes often look thinner when reversed, and some designs need a slightly heavier reverse version.
• One color on a mid-tone background. For example, a gold logo on kraft paper.

Why this matters: stamps, embossing, foil, embroidery, laser engraving, screen printing, fax and many receipt printers all reproduce one color. If the design depends on two colors touching to separate shapes, it will break in those places.

3. Contrast and color checks

• Light and dark backgrounds. Check the logo on white, black, and the actual colors of your website in light and dark modes.
• Text-level contrast for wordmarks. If the logo contains words that must be read, aim for strong contrast against its background. WCAG, the web accessibility guidelines, recommends a contrast ratio of at least 4.5:1 for normal text and 3:1 for large text. Logos are exempt from WCAG’s contrast requirement, but meeting it is still good practice.
• Grayscale. Convert to grayscale. If two colors become the same gray, the design relies on hue alone.
• Color vision deficiency. Use a simulator (built into many design tools and browser developer tools) to check that the logo still works for common types of color blindness, especially red/green.

4. Legibility check

For letter-based logos, the real test is whether people see the letters you intended.

• Cold read. Show the monogram to someone who does not know your name for a few seconds and ask what letters they saw.
• Orientation. Check letters that look similar when rotated or mirrored, such as N and Z, M and W, or b, d, p and q in lowercase marks.
• Accidental words or shapes. Look at the monogram upside down and at a glance. Read the initials aloud in every order you use.
• Script letters. In script monograms, check commonly confused capitals such as I and J, T and F, S and L.

5. Real-world mockups

Place the logo where it will actually live, at real size:

• Browser tab (upload a test favicon or view a screenshot at 100% zoom)
• Social avatar in a circular crop
• Website header on mobile, around 360 pixels wide
• Business card or invitation printed on your office printer
• Email signature
• Product, packaging, sign or garment, as relevant

A circular crop deserves special attention for monograms: letters that touch the edges of a square canvas will be clipped.

6. Distinctiveness and trademark basics

This section is general information, not legal advice. Trademark law varies by country, and a qualified trademark attorney can tell you how it applies to your situation.

Letter-based logos carry particular risks: there are only so many letter combinations, and many businesses use the same initials. Before you invest heavily in a logo, do some basic research.

Search official databases

• United States: the USPTO’s trademark search system on uspto.gov.
• European Union: the EUIPO’s search tools, and TMview, which covers many national offices.
• International: WIPO’s Global Brand Database.
• Your own country’s trademark office, if it is not covered above.

Search for your letters as text, and look at the results in classes relevant to your business. Trademarks are registered for specific goods and services, organized internationally under the Nice Classification’s 45 classes.

Search the market

• Search the web, app stores and social platforms for your initials alongside your industry.
• Look for competitors or nearby businesses using similar-looking monograms.

Understand the limits

• A clear database search does not guarantee a logo is safe to use; unregistered marks can also have rights in many countries.
• Simple letter combinations in standard fonts are generally harder to protect than distinctive designs.
• If you plan to register your logo or build a significant business around it, consult a trademark attorney before launch, not after.

7. Files and consistency

• Master vector file saved (SVG; PDF or EPS if needed)
• Full-color, one-color black and one-color white versions
• Small-size simplified version, if needed
• Favicon and app icon exports
• Colors recorded as hex and RGB values, plus CMYK or spot equivalents if you print
• Font names and license records saved

Our logo file formats guide lists exact sizes for each export.

A condensed checklist

[ ] Readable at 16px and 32px (or has a small-size version)
[ ] Works in one color, black and white, and reversed
[ ] Holds up in grayscale and on light and dark backgrounds
[ ] Letters read correctly to someone who doesn't know them
[ ] Survives a circular avatar crop
[ ] Mockups checked at real size
[ ] Basic trademark and market search done
[ ] Vector master and all exports saved

Building testing into the design process

Running these tests after a logo is “finished” often means starting over. It is better to test candidates while you are still choosing. InitialAI is being built to show your monogram at favicon, avatar and print sizes alongside a single-color preview, so weak options are obvious early. Until then, the checklist above takes about an hour with any design tool, and pairs with our guide on choosing fonts for a logo for the legibility side.