Interface Essential

Business

Images Photography

Money Shopping

Programming

Computer Devices

Phone

Mail

Map Travel

Food Drink

Nature Ecology

Entertainment

Shipping

Culture

Health

Work Education

Artificial Intelligence

Arrows

Streamline 3.0

Ultimate

Core

Flex

Sharp

Plump

Micro

Freehand

Streamline Material

Nova

Cyber

Streamline Vault

Logos

Pixel

Google Material

Tabler

Remix

Feather

Iconoir

Carbon

Solar

Lucide

Brand Logos

Bootstrap

Atlas

Unicons

Ionic Icons

Phosphor

MingCute

Font Awesome

Majesticons

Mynaui

Radix

Heroicons

Flagpack

Pi Symbol Circle

Pi Symbol

<p>Core is the Helvetica of icons. The Solid variant provides filled shapes for a bolder, more impactful appearance while maintaining legibility at small sizes.</p>

Core Solid

**Summary**: Core's high-legibility sub-style — opaque fills on rounded 14px-grid silhouettes, the most reliable Core option for active states, dense UI, and small-size contexts. One of the harder sub-styles in the catalog, while rounded silhouettes prevent the full coldness of Sharp Solid. The tone signals clarity on demand: "we are clear and direct when needed." Best for active and selected states paired with Core Line, tab bars, dense data tables, and any context requiring reliable legibility at 12–16px within a neutral design system.

**Last updated**: 2026-04-23

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## Fit & Recommendation

### Primary use cases

- Tab bars and primary navigation in mobile apps
- Compact icon-heavy UI where 1px line icons would disappear
- Feature highlights, badges, and status indicators
- Dense data tables where actions must be visually distinct
- Dense UI at 12–16px — the most reliable Core sub-style at minimum size
- Active and selected states paired with Core Line for inactive

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## Brand & Cultural Identity

### What it communicates

> "We are clear and direct when needed."

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## Visual & Technical Specs

### Visual properties

| Property | Value |
|----------|-------|
| Stroke weight | None |
| Fill | Opaque fill with transparent cutouts — background visible through cutout areas |
| Corner treatment | Rounded silhouettes — same rounded language as Core Line |
| Color | Monochrome |

### Emotional Scores

Core Solid is near neutral on warmth leaning slightly cool — solid black fills are authoritative while rounded silhouettes prevent the full coldness of geometric solid families. It is one of the harder sub-styles in the catalog, as the opaque fill adds substantial visual weight. It is somewhat cold on both friendliness and playfulness, with bold fills reading as direct and assertive while rounded shapes prevent full formality. On its human↔mechanical character, it sits near neutral leaning slightly mechanical — rounded silhouettes retain some human quality while the density of fill reads as systematic.

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## Pairing & Compatibility

### Typography pairing

- **Primary**: DM Sans Medium/SemiBold — weight-compatible with solid fills without going to display-level heaviness
- **Alternative**: Plus Jakarta Sans — humanist warmth at medium weight, appropriate for the slightly bolder Solid register
- **Body**: Inter Regular — the standard neutral body pairing
- **Avoid**: Ultra-light or hairline fonts — the visual weight imbalance is too extreme


<p>The Helvetica of icons. Core is stripped to essential form with generous spacing. It's a timeless workhorse for interface design.</p>

Minimal icons

Mathematics

Pi Symbol icon - Core Solid Set

Download Pi Symbol SVG vector or transparent PNG icon in Solid, Minimal, Glyph, Wireframe style(s) for Sketch and Figma. It belongs to Core Solid vectors SVG collection.