Three months back, we announced our transition toward a binary file format and explained how the technology has achieved a 100x reduction in the file size of ROBLOX places and a 5-10x reduction in load/save time. We have been rolling out the new format transparently and carefully, starting with the temporary files created for “Play Solo” and “Start Server” sessions in ROBLOX Studio. This week, we finished applying the format to all of ROBLOX, including Personal Build Server saves, and local place saves, loads and uploads via ROBLOX Studio.

You can look back at our original tech article about the binary file format to understand how re-arranging data makes it work and see the results of a couple tests we ran to prove its efficacy. If you’re the anecdotal type, however, you can simply experience it for yourself by loading and saving places in ROBLOX Studio, looking at the reduction in local file sizes, and uploading content to ROBLOX.com. In general, you should notice that files are smaller and saving/loading/uploading is faster – especially when you’re working with a place built out of tens of thousands of parts.

While the binary file format is now the default, we’re retaining – in the spirit of being an open platform – the ability to save in XML format. XML is a human-readable, hierarchy-based format, where each object has properties, and each property has a value, and everything fits together in a nice tree of data. It can be useful for debugging purposes, precise testing and understanding how a ROBLOX place works. Simply save your ROBLOX build using File > Save As and select XML as the format.

We performed significant testing over the past three months to ensure the new file format does not break any existing or forthcoming content. As always, let us know if you experience any issues you think might be the result of this file format transition here or on the Help forum. The more detail you can provide, the more your report will help us.