Favicon at 512 by 512
512 by 512 is the largest icon in a standard favicon set, used by web app manifests and install prompts. It is 1:1 and comes to 0.26 megapixels.
At a glance
- Dimensions
- 512 × 512 pixels
- Simplified aspect ratio
- 1:1
- Decimal ratio
- 1:1
- Megapixels
- 0.26 MP (262,144 pixels)
- CSS aspect-ratio
- aspect-ratio: 1 / 1;
- Preset category
- Design
- Where it is used
- The largest icon in a favicon set, referenced from a web manifest
In detail
A favicon is not one file. A complete set spans a browser tab at sixteen pixels, a bookmark bar, a home screen shortcut and an install prompt, and the 512 pixel version is the top of that range: it is the size a web manifest references for the largest install and splash contexts.
Designing at 512 and letting everything downscale is a mistake, and it is why so many favicons look like grey smudges in a tab. A mark that works at 512 usually has detail that vanishes below 32, so the discipline is to design the sixteen pixel version first, or at least check it, and then scale the concept up rather than down.
The favicon generator here outputs PNGs at 16, 32, 48, 64, 96, 128, 180, 192 and 512 pixels, a real .ico file packing the 16, 32 and 48 versions together, a web manifest and an HTML snippet for the head. That covers the tab, the bookmark, the home screen icon and the install prompt from a single source image.
The image resizer also has square icon presets, at 16, 32, 64, 128 and 256 pixels. That set is deliberately smaller than the favicon generator's, so for a full favicon set the generator is the right tool and the resizer is for one off square exports.
Examples
{
"icons": [
{ "src": "/icon-192.png", "sizes": "192x192", "type": "image/png" },
{ "src": "/icon-512.png", "sizes": "512x512", "type": "image/png" }
]
}512 x 512 install prompt and splash
192 x 192 home screen shortcut
48 x 48 bookmark and legacy contexts
32 x 32 high density browser tab
16 x 16 browser tab: the one that decides if the mark worksThings that catch people out
- A detailed mark scaled down to 16 pixels becomes an unreadable blob. Check the smallest size before finishing the largest.
- A single 512 pixel PNG is not a favicon set. Older contexts still expect an .ico containing the small sizes.
- The image resizer's icon presets stop at 256, so use the favicon generator when you need the full set including 512.
Try it: Aspect Ratio Calculator
Enter a width and a height, or a ratio and one dimension, and it solves the missing one, simplifies the ratio, counts the megapixels and gives you a copyable CSS value.
Aspect Ratio Calculator
LOCAL · Browser-OnlyCalculate and convert aspect ratios for images, videos, and screens
1920 x 1080px · 16:9 · 1.7778:1
Common Aspect Ratios Reference
| Ratio | Decimal | Common Use |
|---|---|---|
| 16:9 | 1.778 | Widescreen TV, YouTube, monitors |
| 4:3 | 1.333 | Classic TV, iPad, presentations |
| 1:1 | 1.000 | Instagram square, profile pictures |
| 21:9 | 2.333 | Ultrawide monitors, cinema |
| 9:16 | 0.563 | Phone vertical, TikTok, Reels |
| 3:2 | 1.500 | 35mm photography, MacBook |
| 2:3 | 0.667 | Portrait photography, posters |
| 5:4 | 1.250 | Large format photography, older monitors |
| 32:9 | 3.556 | Super ultrawide monitors |
| 2.39:1 | 2.390 | Anamorphic cinema, widescreen films |
Related Image and canvas sizes
All image and canvas sizes →iOS app icon size: 1024 by 1024
The 1024 by 1024 app icon master, why the corners should be left square, why transparency is a problem, and how the smaller sizes derive from it.
1:1 aspect ratio
The square ratio, its origins in medium format film and social feeds, why it is the most reusable shape, and where it wastes space.
OG image size: 1200 by 630
The 1200 by 630 open graph image, why it became the default sharing size, the markup that nominates it, and the rules that make it actually appear.
16:9 aspect ratio
Where the 16:9 ratio came from, the pixel dimensions that hit it exactly, what it suits, and the places where a widescreen frame is the wrong shape.
4:3 aspect ratio
The 1.333 ratio that ran television and computer monitors for decades, where it still appears today, and how it compares to the widescreen shapes.
21:9 aspect ratio
The 21:9 marketing label at 2.3333, the 43:18 and 64:27 shapes that real ultrawide panels actually use, and how to design for the gap between them.
Tools for this
- Favicon Generator Free online favicon generator - generate favicons from text, emoji, or uploaded images in all required sizes
- Image Resizer Free online image resizer - resize images to exact dimensions, percentage, or common presets