Workflows, Privacy & Cost Guides
Privacy-First Financial Spreadsheets vs Telemetry-Heavy Office Suites
When Arte Sheets fits best
- Zero-account local mode: calculate, chart, and export .xlsx/.csv files in your browser with zero server storage of workbook contents.
- EU-hosted cloud infrastructure (Hetzner Online GmbH, Germany) on both Free and Pro—no Enterprise add-on needed for EU data residency.
- Strict AI & connector boundaries: saving a cloud workbook never sends data to AI providers, and local-only workbooks are inaccessible to external connectors.
When Telemetry-Heavy US Cloud Office Suites fits best
- Air-gapped open-source desktop LibreOffice Calc on an encrypted offline disk eliminates browser environments altogether.
- Enterprise Microsoft 365 E3/E5 or Google Workspace Enterprise offer SOC2/ISO27001 admin compliance, DLP policies, and customer-managed encryption keys for large corporations.
Verifiable Privacy Controls: Local Browser vs EU Cloud vs Big-Tech Suites
Privacy claims only matter when backed by concrete architectural boundaries. In Arte Sheets, the public Service Worker caches only static application shell files (JS, CSS, fonts, icons)—explicitly excluding API, billing, account, and document payloads from CacheStorage.
When you sign in to use My files, credentials use salted cryptographic password hashes with HttpOnly, Secure, SameSite=Lax cookies, and cloud workbooks sit behind per-user server authorization in Germany—never in public S3 buckets.
| Privacy Dimension | Arte Sheets | Consumer Cloud Suites (M365 / Google) | Offline LibreOffice Calc |
|---|---|---|---|
| Edit .xlsx/.csv without an account | Yes — local IndexedDB mode | No — Microsoft or Google identity required | Yes — local OS disk |
| Default cloud auto-upload | Off until you sign in & save to My files | On by default (OneDrive / Google Drive) | None |
| Cloud data residency (standard tier) | European Union (Hetzner, Germany) | Global / US regions (EU lock requires Enterprise) | N/A (local disk) |
| Data controller jurisdiction | EU GDPR (Arte Soft EOOD, Bulgaria) | US parent corporations (GDPR SCCs/DPF) | Local user |
| Marketing email & ad profiling | Zero ads; SES EU used strictly for auth/recovery | Ecosystem cross-promotion & connected telemetry | None |
| Self-service data portability & erasure | Download .xlsx + account .json export + full account deletion | Account privacy dashboards / Takeout | Delete local file |
How AI and Connected Apps Respect Workbook Privacy
A major fear with spreadsheet AI in 2026 is silent background indexing or training on confidential financial sheets. Understanding exact data flows in Arte Sheets lets security-conscious analysts use AI selectively or avoid it completely:
| Workflow | Leaves Your Browser? | Sent to AI Provider? | How You Stay in Control |
|---|---|---|---|
| Anonymous local workbook editing | No | No | Stays in browser IndexedDB; export .xlsx locally |
| Public /en/learn/ on-page practice table | No | No | Runs client-side in practice-engine; never saved to account |
| Saving workbook to My files (EU cloud) | Stored in Germany (Hetzner) | No | Private per-user storage; never shared or sent to AI automatically |
| Using in-app Pro AI assistant | Yes, for your explicit request | Yes (bounded selection/excerpt) | Only runs when you submit a prompt; respects document permissions |
| Optional ChatGPT / Codex connector | Only if authorized on shared cloud doc | To connected app you approved | Cannot access browser-only files; revocable anytime in Account |
Cost of Privacy-First Spreadsheet Workflows
Unlike enterprise SaaS vendors that charge custom Enterprise uplift fees just to store spreadsheets inside the European Union, Arte Sheets provides local browser privacy and German EU cloud hosting right on the $0 Free plan.
| Solution | Price | EU Storage Included | Best Fit |
|---|---|---|---|
| Arte Sheets Free | $0 | Local browser + 10 German EU cloud workbooks | Private net-worth, payroll & client .xlsx/.csv analysis |
| Arte Sheets Pro | $19.99/mo or $179.99/yr | 1,000 German EU cloud workbooks (1 GiB) | EU professionals wanting opt-in AI, Goal Seek, Macros & 62 courses |
| LibreOffice Calc | $0 | Local disk only | Air-gapped workstations needing zero browser or cloud features |
| Enterprise Cloud Office Suites | $22–$57+/user/mo | EU Data Boundary on eligible Enterprise SKUs | 1,000-seat corporations requiring SSO, Purview DLP & eDiscovery |
Frequently asked questions
Does Arte Sheets store my credit card details when I subscribe to Pro?
No. Payments are processed by Stripe; Arte Sheets never receives or stores your card number, CVC, or bank credentials, retaining only Stripe billing references needed for entitlements and statutory EU tax law.
Can I export all my account metadata and permanently delete my Arte Sheets account?
Yes. Signed-in users can download any cloud workbook as .xlsx, download a machine-readable .json export of their account/progress/billing metadata, and permanently delete their account and cloud workbooks from the Account dialog.
Can the optional ChatGPT connector read my local browser-only spreadsheets?
No. Local-only workbooks stay in your browser IndexedDB and are completely inaccessible to account connectors. Note also that the ChatGPT plugin is currently under review rather than publicly promised.
What should I avoid sending if I email Arte Sheets support?
Never email passwords, sign-in codes, payment details, API keys, or confidential client workbooks; a small invented example is safest for reproducing spreadsheet questions.