Privacy Policy

1. Introduction

eCircuitCalc (the “Website”) is a free online suite of electronics and electrical engineering calculators, unit converters and educational tools operated by https://ecircuitcalc.com/ (“we”, “us”). This policy explains what information the Website collects, how it is used, and the choices you have. It is written to reflect the Website's actual, current technical implementation.

2. Information We Collect

• Contact form submissions: when you send a message via the Contact page, we receive the name, email address, subject and message you provide, plus the timestamp and IP address recorded by our server for delivery and abuse protection.
• Local, device-side storage (no data sent to us): your dark/light theme preference (ecc-theme) and your cookie-consent choice (ecc-consent) are stored in your browser's localStorage. We do not receive or store these on our servers.
• Usage data via Google Analytics — only with your consent: when you allow analytics cookies, Google collects standard analytics data (see Section 5).

We do not require accounts, and we do not collect payment data, biometric data, or special-category personal data.

3. How We Use Information

• To deliver the calculators and tools you use.
• To respond to messages sent through the contact form.
• To detect and block spam and abuse of the contact form (rate limiting, hidden “honeypot” field).
• With your consent, to understand aggregate usage and measure advertising effectiveness.

4. Cookies and Similar Technologies

Analytics and advertising cookies are not set unless you choose to allow them via the cookie banner or “Cookie Settings” in the footer. You can withdraw consent at any time; changes apply from that moment onward.

5. Google Analytics (GA4)

With your consent, the Website uses Google Analytics 4 (measurement ID G-XXXXXXXXXX) to understand how visitors use the site in aggregate. The GA4 tag is loaded only after you grant analytics consent, and Google's Consent Mode is used to signal analytics_storage state. Google may process your IP address and usage data as described in Google's Privacy Policy and its documentation on how Google uses data it receives from our partners. You can opt out of GA4 cookie use with Google's Analytics opt-out browser add-on.

6. Google Ads and Advertising

No advertising as of this time.

7. Legal Basis for Processing (where applicable)

• Consent — analytics and advertising cookies (withdrawable anytime via Cookie Settings).
• Legitimate interest — operating the Website, responding to your contact messages, and basic security/abuse prevention.
• Performance of a service — processing your contact message so we can reply.

If you are in a jurisdiction with specific rights (GDPR/UK GDPR, ePrivacy, CCPA/CPRA, the Philippine Data Privacy Act, or others), the rights below describe what we honor in practice.

8. How We Share Information

We do not sell personal information. Contact-form data is processed by our hosting and email-delivery infrastructure solely to deliver and store messages. With your consent, usage/advertising data is processed by Google as a service provider under the arrangements described in Google's policies. We may disclose information if required by law.

9. Data Retention

• Consent & theme preferences: held only in your browser until you change or clear them.
• Contact messages: retained as needed to respond and for reasonable records purposes, then deleted.
• Analytics/advertising data: retained by Google under its own retention settings; you can control much of this via Google Ads Settings and the opt-out tools above.

10. International Data Transfers

Google's services process data in the United States and other countries. When we use Google services with your consent, data is transferred under the arrangements described in Google's Privacy Policy, including applicable safeguards for international transfers.

11. Your Privacy Rights

Depending on where you live, you may have some or all of the following rights, which we honor to the extent they apply:

• Access / know what personal information we hold about you (contact messages).
• Rectification and deletion of your contact-form data.
• Withdrawal of consent for analytics/advertising at any time via Cookie Settings.
• Opt-out of analytics via Google's opt-out tools (Section 5).
• CCPA/CPRA: we do not “sell” or “share” personal information for cross-context behavioral advertising; you may request access, deletion, or correction by contacting us.
• Philippine Data Privacy Act: you may access, rectify, or object to processing, and may lodge a complaint with the National Privacy Commission.

To exercise any right, contact us using the details in Section 14.

12. Children's Privacy

The Website is a general-audience engineering tool. We do not knowingly collect personal information from children under 13 (or under the relevant age in your jurisdiction). If you believe a child has provided us information, contact us and we will delete it.

13. Data Security

We use HTTPS for all requests, keep email credentials and API secrets server-side in environment variables (never in website code), validate and sanitize all form input, and apply rate limiting and anti-spam controls to the contact form. No method of transmission is 100% secure, but we work to protect your information using commercially reasonable measures.

14. Changes to This Privacy Policy

We may update this policy as the Website evolves. If we make a material change to our cookie or data practices, we will update the “Last Updated” date below and — where required — ask you to re-confirm your cookie preferences (our consent system is versioned for exactly this purpose).