Law of Similarity
Users automatically group similar-looking elements, making relationships clear and navigation intuitive.
Definition
The Law of Similarity states that your users instinctively group UI elements that look alike into a single perceived unit.
It’s one of the Gestalt principles of visual perception, rooted in how our brains pattern-match and seek efficiencies.
When elements share color, shape, size, or style, users assume they’re related, so you can guide attention and clarify hierarchy without extra text or arrows.
Mastering similarity isn’t just fancy design theory, it’s a cognitive shortcut that reduces cognitive load, speeds up interpretation, and makes interfaces feel intuitive.
Real world example
Think about the Google Docs toolbar: icons share consistent color, stroke weight, and shape language. That similarity tells you these controls belong in one cluster, editing tools, so you scan faster and act with confidence.
Real world example
In navigation menus, applying consistent icon style, spacing, and color signals which links belong together. In form fields, grouping related inputs, like billing vs. shipping, via matching borders or background hue highlights their relationship. In dashboards, using uniform card dimensions, typography scale, and accent colors across data widgets instantly communicates they’re part of the same information set.
What are the key benefits?
Everything you need to make smarter growth decisions, without the guesswork or wasted time.
Use consistent color palettes for related buttons or links.
Match shape and border style to group controls logically.
Standardize iconography across similar functions.
What are the key benefits?
Everything you need to make smarter growth decisions, without the guesswork or wasted time.
Don’t mix button styles in the same action group.
Avoid inconsistent spacing that breaks visual grouping.
Don’t introduce random colors that confuse relationships.
Frequently asked questions
Growth co-pilot turns your toughest product questions into clear, data-backed recommendations you can act on immediately.
How does Law of Similarity differ from proximity?
Similarity groups elements by shared visual traits like color or shape, whereas proximity relies purely on spatial closeness. You need both: proximity defines clusters; similarity signals shared purpose within them.
Can too much similarity be harmful?
Yes, overusing similarity can create a flat, indistinct UI where everything looks related. Introduce deliberate contrast for hierarchy and to avoid visual monotony.
What visual properties trigger similarity most effectively?
Color, shape, size, and texture are the strongest cues. Icons with the same stroke weight or buttons sharing the same hue are instantly perceived as a set.
Is similarity effective for accessible design?
Absolutely, but pair it with other cues like labels or patterns for color-impaired users. Don’t rely on color alone, use shape or iconography too.
How do I test if my similar elements actually feel grouped?
Run quick hallway tests: show colleagues screens for five seconds, then ask them to tell you which controls belong together. If they point out unexpected groupings, iterate your visual patterns.
Harness Similarity Now
Stop user confusion caused by inconsistent visuals. Run your key screens through CrackGrowth’s diagnostic to pinpoint where mixed styles are sabotaging your clarity.