A Satisfactory save viewer that never uploads your save

When you drop a save on a website, the fair question is where it goes. On Factory Board the answer is: nowhere. Here is how that works, in plain terms, and how you can check it yourself.

The save stays in the tab

A Satisfactory save is a file on your disk. When you drop it on the page, your browser hands the file to the page, and the page reads it right there, in a background worker inside the same tab. The worker turns the file into a list of machines, belts, power grids and containers. The board is drawn from that list.

There is no server behind this step. Nothing about your factory is sent anywhere, and there is no account to make. What the page remembers between visits, such as your plan and a short history of the saves you dropped, stays in your own browser's storage. The file on your disk is never changed either: the board only reads, so it cannot break a save.

The recipe book

To say why a line is slow, the board needs the game's recipes: what each machine takes and makes, and how fast. The page carries a recipe book extracted from the game, and the header names the game build it came from. After a patch, a new recipe can be missing from it for a while, and the page says how many of your lines it does not know.

If you would rather use your own install's recipes, drop the game's en-US.json on the page. It is in your Satisfactory install, under CommunityResources\Docs. It is read in the tab the same way, and kept in your browser for next time. Forget, in the header, puts the page's own book back.

What the page does count

We count visits, with our own counter. It sets no cookies. Besides page views it records five fixed things: a save was dropped, a save could not be read (with one of four coarse reasons, such as too big or an unsupported game version), a recipe book was loaded, the demo was opened, and a result was copied to share. Nothing read from a save can travel with any of them. Dropping saves five times in one visit counts as one try.

We count so we know whether anyone uses the board, and whether saves from a new game version start failing.

Check it yourself

Open your browser's developer tools, go to the Network tab, and drop a save. The board fills in, and no request carries the file anywhere. The page's security policy only allows connections to itself and to the counter, so it could not send the file elsewhere if it tried.

The code is public too, at https://github.com/ludvenhq/factory-board.

https://factory-board.ludven.com