TarifDelta
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🔒 Files processed locally
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Privacy

Your supplier price lists stay on your device.

Core principle: the contents of XLSX, XLS and CSV files imported into TarifDelta are read, compared, and exported locally by your browser.

Imported files

TarifDelta does not send the contents of your supplier price lists to an application server and does not create a server-side history of comparisons. Data stays in the browser tab memory while you use the service.

Account, access, and local storage

The free comparison and one-off offer do not require an account. Pro uses an account so the subscription can be recognised across devices. TarifDelta then stores the email address, a cryptographic derivative of the password, login sessions, and the technical identifiers needed to link the account to Stripe. The main password derivation happens in the browser and the server stores only an additional hash; the plaintext password is never stored. No supplier-file content is saved in the account.

TarifDelta does not install advertising cookies, pixels, or analytics tools. A strictly necessary secure session cookie, inaccessible to JavaScript, is used when a user signs in to a Pro account. The browser also stores locally whether the free comparison has been used and, after a one-off payment, the Stripe session identifier.

Payment verification

When paid access is activated, TarifDelta may send only the technical identifiers required by a Cloudflare function on the site. For the one-off offer, this includes the Stripe session identifier. For Pro, the account is linked to the Stripe customer and subscription so access can be recognised after signing in on another device. Managing or cancelling a subscription opens the Stripe customer portal without sending supplier files. References, prices, descriptions, imported files, and comparison results are never sent to Stripe or to this function.

Site hosting

The static site is hosted on Cloudflare Pages. As with any website, the host may process technical metadata related to page loading, such as the IP address, browser, or request date. Supplier-file contents are not transmitted to TarifDelta during analysis.

Exports

CSV and XLSX exports are generated in the browser and downloaded directly to your device.

Excel dependency

The SheetJS library used to read and generate workbooks is served from the same site as a local copy. No third-party CDN is contacted during use.

Limitations

TarifDelta does not control your browser extensions, software installed on your computer, or operating-system file-sync services. For sensitive data, use a computer and browser you control.

Contact and support

For any question about TarifDelta or your access, contact tarifdelta.pro@gmail.com.

Last updated

Last updated: 27 September 2026.

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