Privacy Policy

Last updated: November 14, 2026.

The short version: signed out, your plans stay in your browser. Signed in, the plan you work on is saved to your account on our servers. We collect anonymous usage counts. An AI app you connect receives the plan it works on. This page explains the details for usebldg.com and the bldg editor. Questions: hello@usebldg.com.

Signed out: plans in your browser

You need no account to use the editor. Until you sign in:

The editor runs in your browser. The plan you work on, your recent plans, saved versions, edit history and settings are kept in your browser's own storage on your device. We cannot see them.
Save and the exports write files to your computer. Nothing is sent to us.
Delete them at any time by clearing this site's data in your browser.

Signed in: plans in your account

What is saved. While you are signed in, the plan you work on is saved to your account automatically: the plan that is open when you sign in right away, and any other plan from your first change to it. An empty new plan you have not drawn on is not saved. We store the plan, its full history with who made each change (you, or an AI app you connected), and the project name.
Where. On Cloudflare's servers in the United States.
Who can see it. You, and the AI apps you connected, which reach only your projects. We look at your data only to keep the service running or when you ask us for help.
Deleting it. Move a plan to the trash from the editor or your account page; it stays there for 30 days, and you can bring it back or delete it forever. You can also delete your account, which deletes your plans with it.
Signing in. Sign-in is run by WorkOS. We receive your name, your email address and the sign-in method you used (Google, Microsoft or email).

Copy link does not upload the plan to us: it puts the whole plan in the part of the link after #. Browsers never send that part to a server, so the plan does not reach our server when someone opens the link (the link of a plan in your account, usebldg.com/p/…, is different: it only opens the plan for you, after you sign in). Anyone who has the copy link can open the plan, so share it only with people who may see it.

AI apps you connect

You can connect an AI app, such as Claude or Claude Code, to your account (Edit with Claude). The app receives the plan it opens, and reads and changes your projects through bldg, as you allow it.
What the app does with the plan it receives is covered by the privacy policy of its own company, not this one.
You can disconnect an app at any time on your account page.

AI assistant with your own key

The AI assistant is optional. It uses an API key that you enter, for a provider that you choose (for example Anthropic, Amazon Bedrock, OpenAI or Google Gemini).
AI requests go directly from your browser to that provider, with your key. They do not pass through our servers, and we never see your key, your messages or your images. (If you are signed in, the plan itself is saved to your account as described above, but the assistant's requests are not part of that.)
What you send to the provider (your messages, the parts of your plan the assistant reads and any images you attach) is handled under that provider's own privacy policy.
Your key stays in your browser: for the current tab by default, or on this device if you choose "Remember on this device". Forget key removes it.

Anonymous usage counts

The editor and this site send a small named event (for example that a page was opened or that a first edit was made) with a random id kept in this browser. The id is not tied to an account, and an event never holds a plan, a file name, an address, an email or an AI key. Events are deleted after 13 months. Signed in, our server also counts a few account events (that you signed up, connected an AI app, that it made its first change, that you came back). No third-party analytics, no advertising. We do not sell or share personal information.

Other services the editor can use

Pick on map (in the project settings) loads map tiles from OpenStreetMap and sends the place you search for, or the point you pick, to OpenStreetMap's place search (Nominatim). It runs only when you open the map.
Like every website, the servers that host usebldg.com receive the basic information your browser sends with each request, such as your IP address, the page asked for and your browser type. Our hosting provider (Cloudflare) may keep it in short-lived logs for security and to run the service. We do not use it to identify or track you.

Feedback and email

If you write to hello@usebldg.com (for example with the editor's Send feedback), we receive your email address and what you write. We use it to answer you and to improve bldg, and we do not sell it. A feedback email contains your plan only if you attach it yourself.

The embedded viewer

When a website embeds a plan with the bldg viewer, the viewer runs in your browser on that website and loads its files from wherever that site serves them (its own server or a CDN such as jsDelivr). It sends nothing to us. That website's own privacy policy applies to it.

Children

The site is not directed to children under 13, and we do not knowingly collect information from them.

Changes to this policy

We may update this policy. The date at the top says when it last changed.

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