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Autosave

Buildopia automatically saves a copy of your build in the browser as you work. This means a stray keyboard shortcut, an accidental tab close, or a phone call mid-session won't cost you your progress. Autosaves are now surfaced directly in My Builds, where you can browse, load, or promote any of the last 30 snapshots. This guide explains how autosave works, when it saves, and what it can't do.

When It Saves

Autosave triggers in two situations:

• Shortly after you stop editing. A few seconds of inactivity after a placement, paint stroke, or erase triggers a save in the background. You won't see a spinner or any loading state — it happens silently.
• Immediately when you switch away. If you switch to another browser tab or app, Buildopia saves right away before the page goes into the background. This means even a quick alt-tab won't lose recent changes.

There's no manual save button for autosave and no need to remember to trigger it. It runs automatically as long as you have the page open and have made changes since the last save.

Where Autosaves Live — My Builds

Every autosave is also written into the Autosaves tab in My Builds, which keeps a rolling window of the last 30 snapshots. You can open My Builds from the top bar or the main menu and switch to the Autosaves tab to see them — each one is labelled by number (newest first) and shows the exact date and time it was taken.

From the Autosaves tab you can:

• Load any snapshot to jump back to that exact state of your build.
• Save to My Builds to promote a snapshot into a permanent named save on the Saved Builds tab, where it won't be pushed out by newer autosaves.

The rolling window keeps the 30 most recent entries. Once the cap is reached, the oldest is removed automatically to make room for the next one.

The Startup Restore Prompt

The next time you open Buildopia in the same browser — whether that's seconds later or days later — the app checks whether an autosaved build is waiting. If one is found, a prompt appears with two options:

If you choose Store, the build is written into the Autosaves rolling window. It will eventually be pushed out if 30 newer autosaves accumulate — use Save to My Builds to give it a permanent name if you want to keep it indefinitely.

What Autosave Can't Do

Autosave uses browser-local storage, which means it has some hard limits:

• It doesn't follow you across devices. A build autosaved on your laptop won't appear on your phone, and vice versa. Each browser instance has its own separate autosave history.
• It doesn't survive browser data clearing. If you clear your browsing history, cookies, or site data, both the autosave and the entire My Builds Autosaves history are wiped. Export any build you want to keep before doing this.
• It doesn't work across different browsers. An autosave in Chrome won't be visible in Firefox or Safari, even on the same device.
• The rolling window is capped at 30. Autosaves beyond the most recent 30 are deleted automatically. If you want to preserve a specific snapshot permanently, use Save to My Builds.

Export as Your Real Backup

The Export button in the sidebar saves a complete .json file to your downloads folder. This file can be loaded back into Buildopia at any time, on any device, in any browser. Unlike autosave, it survives browser resets, device switches, and doesn't get pushed out by new work.

A good habit is to export at the end of each session — or at any major milestone, like completing a floor or finishing an exterior — so you always have a known-good checkpoint to fall back to. See the Importing & Exporting guide for the full details.

What Autosave Preserves

Each autosave is a full snapshot of your build at the moment it was triggered, including:

• Your grid dimensions (Width, Height, Length).
• Every block placed — shape, material, rotation, and colour tint.
• The current Blueprint Reveal level.
• Your Placement Size settings.

It does not preserve the camera angle, active tool, or undo history — those reset when you return to the page, the same way they would after a normal page load.

Autosave in Private Browsing

In private/incognito browsing mode, most browsers block or restrict local storage and IndexedDB — which is how autosave and My Builds both work. In these sessions, autosave may not function at all, or may save but not survive closing the tab, and the Autosaves tab in My Builds may be empty or unavailable. If you're building in a private window, treat each session as if autosave doesn't exist and Export your work before closing the tab.

If the Restore Prompt Doesn't Appear

If you return to Buildopia and no restore prompt appears, it means either:

• There's no autosave stored — this is the case the very first time you open Buildopia, or if there was nothing to save from the previous session.
• The autosave was cleared by a browser data wipe.
• You're in a private browsing session where storage is blocked.
• You're opening Buildopia in a different browser than where you saved.

In any of these cases, check the Autosaves tab in My Builds — if snapshots were written during a previous session in the same browser, they'll be listed there even when the startup prompt doesn't appear. If nothing shows up there either, the saves were most likely cleared along with your browser data. This is why exported .json files are the recommended primary backup — they're immune to all of these situations.

Autosave & Community Builds

Loading a build from Community Builds replaces your current build — and triggers an autosave of the community build shortly after loading. If you had your own work in progress when you opened Community Builds, export it first or save it to My Builds before loading anything. Once the community build is loaded and autosaved, your previous work's autosave slot is overwritten — though any earlier snapshots may still be visible in the Autosaves tab.