1. 100% クライアントサイド動作設計
Unlike traditional web tools that send your inputs to remote cloud servers for processing, WorldTimeBase executes all mathematical operations—including world clocks, time zone conversions, solar algorithms, and duration calculations—entirely inside your browser's local memory.
Zero Server Logging
When you convert a time zone or search for a city, that request is never sent to our servers or logged in any backend database.
Static Delivery
Our infrastructure delivers pre-compiled, static HTML, CSS, and JavaScript. Once delivered, calculations run offline and autonomously.
2. ブラウザローカルストレージ（localStorage）の利用
To provide a convenient user experience, WorldTimeBase utilizes your browser's local storage (localStorage) to persist your display preferences across visits:
- Pinned Clocks: The list of cities you have pinned to your World Clock dashboard.
- Display Settings: Your choice of 12-hour or 24-hour time format, seconds display, and analog dial preferences.
- Visual Theme: Your dark mode or light mode appearance preference.
This data never leaves your device. It is never transmitted across the network, and you can clear it at any time by clearing your browser cache and site data.
3. 端末の位置情報（ジオロケーション）権限について
Certain astronomical tools (such as the Sunrise & Sunset calculator) offer an optional "Use My Location" button. If you explicitly grant permission:
- Your coordinates are retrieved by your browser's native Geolocation API.
- The coordinates are fed directly into the client-side NOAA solar equations to determine local solar noon and twilight hours.
- Your coordinates are never saved to remote servers, never logged, and never shared with third parties.
4. クッキーおよび第三者追跡コードの不使用
WorldTimeBase operates a strict Zero-Cookie Policy:
- No advertising cookies or marketing pixels are used.
- No cross-site tracking or behavioral profiling scripts are loaded.
- No external telemetry services monitor your keystrokes or activity.
5. 法的規制への適合（GDPR、CCPA、個人情報保護法）
Because WorldTimeBase does not collect, process, or store personal data (PII):
- GDPR (EU): We process zero European citizen personal data, meaning no consent banner is required for basic tool operation.
- CCPA / CPRA (California): We do not sell or share personal information as defined by California consumer privacy laws.
- Data Retention: We store zero user records; therefore, there is no personal data retention window.
6. ご質問とデータに関する権利
If you have questions regarding our privacy architecture or technical implementations, please contact our team via the Contact & Support page.
Effective Date: January 1, 2026. This policy applies to all pages and tools on the WorldTimeBase platform.