B0BaseCero

Your money,
from zero.

An open source, fully offline personal finance app. Payday-to-payday periods, category budgets and shared expenses — no server, no accounts, no cloud.

Open BaseCero View the code

Everything stays local and offline

No server, no sign-up. Works even without a connection: your data never leaves the device.

Your data is a spreadsheet

Export and import whenever you want, as .xlsx: your data is never locked in.

Payday-to-payday periods

Your month starts when you get paid, not on the 1st. The budget and the “actually available” figure follow that rhythm.

Shared expenses and budgets

Settle up shared expenses between two people and keep every category under its limit, period after period.

Inside the app

BaseCero Home screen: what’s left for the period, amount spent, income, savings and today’s spend by category. Transactions screen: the period’s expenses grouped by day, each with its category and amount. Net Worth screen: total net worth, active accounts and savings goals. Budget screen: spend per category against its limit, with a progress bar and an over-budget warning.

Install it on mobile or desktop

Android / Chrome

  1. Open BaseCero in Chrome.
  2. Tap the menu (⋮).
  3. Choose “Add to Home screen” (or accept the install banner).

iPhone / Safari

  1. Open BaseCero in Safari (on iOS, only Safari offers this).
  2. Tap the Share button.
  3. Choose “Add to Home Screen”.

Desktop

  1. Open BaseCero in Chrome or Edge.
  2. Click the install icon in the address bar.
  3. Confirm “Install BaseCero”.

Frequently asked questions

Where’s my data?

On your device, in a local database (the browser’s OPFS). BaseCero has no server: nothing leaves that database unless you export it.

How do I back up?

Export a plain .xlsx (to open in Google Sheets or LibreOffice) or a password-encrypted .bce copy. You decide when and where to keep them.

Which banks can I import from?

N26 has a direct import profile with deduplication. For any other bank, a generic assistant maps the columns of its CSV export.

What does it cost, and what’s the license?

It’s free and open source, under the MIT license. You’re free to read, modify and reuse the code.

Does it have analytics or cookies?

None, by design. There’s no server to receive anything you do in the app, so there’s no cookie banner either — there’s nothing to consent to.

What if I lose my device?

The data lives only there. If you hadn’t exported a backup first, it’s gone with the device — that’s why it’s worth exporting copies regularly.