Steam Capsule Analyzer
Enter your App ID, or upload the image itself, and see your small capsule at 231x87, 184x69, 120x45 on the Steam store background, beside real capsules from pages in the same genre at those same sizes. It also measures a handful of things and says, for each one, whether there is a published threshold behind it.
Only three rows can come out as OK or Check, and each has a published source behind it: your uploaded file's dimensions and its aspect ratio, both against Valve's own small capsule spec, and the contrast between your capsule's outer edge and the Steam background. The two dimension rows appear only when you upload the file, because the size of the image Steam's CDN serves says nothing about what you uploaded. Everything else is printed as a raw reading beside the same reading from the peer capsules that loaded. There is no score here, no grade, and no ranking of anybody's page against anybody else's.
Where the 3:1 contrast line comes from
WCAG 2.1 Success Criterion 1.4.11 Non-text Contrast (Level AA)
"The visual presentation of the following have a contrast ratio of at least 3:1 against adjacent color(s)." Checked 2026-09-19.
WCAG is an accessibility standard, not a Valve rule. We borrow it because it is the only published threshold we know of for whether a graphic stands apart from the colour beside it, and we apply it to the band around the outside of your capsule against the Steam store background. A capsule under 3:1 there is one whose edge dissolves into the page it sits on. A dark or vignetted edge can be a deliberate style, so read an amber Check as "go look at it at 120x45" rather than as "this is wrong".
The sizes on this page
You upload the small capsule at 462x174. Steam displays it at 231x87, 184x69, 120x45, per our Steam page asset requirements. Where it turns up: search results, top sellers lists, wishlist rows, curator lists.
From an App ID, the image on screen is the 231x87 rendition Steam serves into those placements, so nothing has to be resampled to show it or to measure it. If that URL does not load we fall back to your main capsule and then to the header image Steam's own API returned, cropped to the small capsule's shape rather than squashed into it, and the line under the previews says which one you are looking at. A URL that does not resolve is not evidence the asset is missing.
The colour behind the capsules is #1b2838, the Steam store page body, the same value this site's Steam page simulation paints. That is the surface the edge contrast row is measured against.
The detail row shrinks your capsule to 120x45, scales it back up to 231x87 and compares what is left with the straight 231x87 rendition. Both readings have to sit on the same pixel grid to mean anything, which is what the round trip is for. It is your capsule measured against itself, which is why it carries no verdict: we have no published number for how much edge detail a capsule should keep on the way down.
Related
- Capsule validator checks your files against Valve's sizes, all five of them.
- Capsule resizer crops one image into every size Steamworks asks for.
- Capsule examples by genre shows the same consented pages, grouped by genre, at every capsule size.
Your capsule is one of the areas the full page analysis covers.