Privacy

Copper has no server of its own. What you enter stays in your browser and, if you turn on sync, in your own Google Drive. We can’t see your book, and we don’t want to.

What stays on your device

Your accounts, transactions, categories, budgets, settings and change history are stored in your browser’s local storage on the device you use. Nothing is sent to us. Copper has no analytics, no advertising and no tracking cookies.

If you sign in with Google

Signing in is optional. If you do, Copper asks Google for:

• Your name, email address and profile picture — to show who is signed in, and to label the changes you make in the Activity history with your first name.
• Access to the Drive files Copper creates or that you choose (the drive.file permission) — to save your book and its backups in a “Copper Expense Tracker” folder in your Drive and keep your devices in sync. Copper can’t see any other files in your Drive.

These requests go straight from your browser to Google. Your sign-in is remembered on your device only — for this browser session, or until you sign out if you choose “Trust this device”.

Copper’s use and transfer of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements. That information is used only to provide Copper’s features to you. It is never sold, used for advertising, or shared with anyone.

Google user data at a glance

• Accessed: your name, email address and profile picture; and only the Drive files Copper creates or that you pick.
• Used for: showing who is signed in, labelling your changes, and saving and syncing your book. Nothing else — no advertising, profiling or AI training.
• Stored: your profile in your browser on your device; your book, its backups and your first name in your own Google Drive. Never on any server of ours — we don’t have one.
• Shared: with no one, except people you yourself share your book with through Google Drive.
• Kept: until you sign out, erase the device or delete the files in your Drive. We hold no copy, so there is nothing for us to keep or delete.

Security

Copper talks to Google directly from your browser over encrypted HTTPS connections. Backup files you download can be locked with a password (AES-GCM encryption); without that password nobody, including us, can open them.

Sharing a book

If you share your book with someone through Google Drive, they can see everything in it — including your first name and device names next to the changes you made. Sharing is always something you start, and you can stop it in Google Drive.

Hosting

The Copper app itself is served by Cloudflare. Like any web host, Cloudflare may briefly process technical details such as your IP address to deliver the site and protect it from abuse. Google’s sign-in screens are covered by Google’s privacy policy.

Deleting your data

• On a device: Settings › Your data › Erase this device.
• In Google Drive: delete the “Copper Expense Tracker” folder.
• To remove Copper’s access to your Google account, visit your Google account’s third-party access page.

Children

Copper isn’t directed at children under 13.

Changes and contact

If this policy changes, the new version will appear here with a new date. Questions? Email us.