Upcoming Change to In-Game Thumbnail URLs

Hello Developers,

We want to inform you of a change we are making to how we handle the thumbnail endpoints that can be used in game. We are making a change to rewrite www.roblox.com thumbnail urls to the rbxthumb contentId format internally so these can be loaded more efficiently.

For example, https://www.roblox.com/asset-thumbnail/image?assetId=26769281&width=420&height=420&format=png will be rewritten to use rbxthumb://type=Asset&id=26769281&w=420&h=420

If you are using these thumbnails in your game they should still work as expected but may be loaded at a different resolution if you are using a size not supported by rbxthumb. If you want to catch any issues in advance and make sure this doesn’t impact your game ahead of time, we recommend switching to rbxthumb ahead of time.

Here are the current supported rbxthumb types and sizes:

"GroupIcon"				"150x150", "420x420"
"AvatarHeadShot"		"48x48", "60x60", "100x100", "150x150", "180x180", "352x352", "420x420"
"Avatar"				"48x48", "60x60", "100x100", "150x150", "180x180", "352x352", "420x420", "720x720"
"AvatarBust"			"50x50", "60x60", "75x75"
"GameIcon"				"50x50", "128x128", "150x150", "256x256", "512x512"
"GameThumbnail"			"768x432", "576x324", "480x270", "384x216", "256x144"
"BadgeIcon"				"150x150"
"GamePass"				"150x150"
"Asset"					"150x150", "420x420", "294x144", "480x270", "768x432"
"BundleThumbnail"		"150x150", "420x420"
"Outfit"				"150x150", "420x420"
"DeveloperProduct"		"150x150", "420x420"

This change will be rolling out early next week.

Please let us know if you see any issues with thumbnails in your game when this starts to be rolled out.


This topic was automatically opened after 16 minutes.

How exactly do we “switch” to this? I don’t think this was specified on this or the rbxthumb topic, and I also have no familiarity with this, so I’m just slightly confused.

Thanks in advance!



If an image is not of a correct size, will it fill or fit?


When you refer to it being loaded at a different resolution, which one will occur? (Does it just form a blank outline or does the image become more blurry?) And if multiple resolutions are available, which will the thumbnail default to?

Other than that, more efficient loading is always awesome. Thank you.


Can we expect to see this change in efficiency and allocating a separate url for loading of image assets used in a similar way for things like the catalog api?


If this could be achieved it would make it much more seamless for developers to make something like an ingame catalog since you wouldnt need to use some sort of proxy or third party service to then return back to the user what the catalogapi returns to the proxy.

However, this is a nice change and hopefully the efficiency of this system will again help developers push the limits.


This would be so much easier for custom loading screens instead of changing every time we updated the Icon!


Now all I want is PromptGroupJoinAsync()


I’ve never used thumbnails before, but at least this make it less complicated to use for other developers


It will fit so it may look blurry depending on what the change in the resolution is. It will default to the closest available resolution (with preference to the same aspect ratio, if available)


When AvatarEditorService is released it will be possible to make an in game catalog without a third party proxy.



Indeed. We do need this. However, Roblox will most likely not recognize it to be a thing. But maybe…


Will these image links continue to work for web applications who use these?


We plan to eventually remove these old urls once traffic becomes low enough. I would recommend switching to use the thumbnails.roblox.com endpoints instead.


In the referenced topic it says this:

RbxThumb is a new ContentId format that allows easy loading of thumbnails. It works everywhere you would expect image ContentIds to work including in ImageLabel.Image and ContentProvider:PreloadAsync.

To switch to it all you have to do is replace whatever you have your image set to with that, could be through a script or manually. Things like ImageLabel.Image, ImageButton.Image, etc.


imageLabel.Image = "rbxthumb://type=Asset&id=26769281&w=420&h=420"

So what I am hearing is, the size for the thumbnails and everything is changing?.

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No, just the URL’s. The sizes of the thumbnails will remain the same. I heard the games page was changing the way they display thumbnails so this may be part of that update.


I’m using the 352x352 size for Avatar Busts in my games. These won’t work anymore because of this change. It does affects some of the thumbnails.


Are we going to have to change all our scripts that use the previous link? And is this change effecting Player thumbnails or headshots etc.

You do not need to change all your scripts to use the new format as we will be automatically rewriting the links internally. Updating your game ahead of time to ensure there is no disruption or bugs is strictly optional.


Does this mean that DevProduct icon scaling, an unfixed issue documented almost three years ago, will also be fixed?

Having to upload thumbnails separately from DevProducts bloats my asset manager and whenever I make a game, I have to construct my entire in-app purchase display system around circumventing this issue.

Really? OP only talks about thumbnails, not any image.

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