Last Updated: 14 April 2026  ·  Version 1.0

Privacy Policy

SigndUp helps you create and manage disposable email accounts for one-time sign-ups. This policy explains exactly what data we collect, how we use it, and your rights.

1. What We Collect

SigndUp collects only the following personal data:

Data Why Stored? Retention
Disposable email address (@signdup.net) Your login ID for one-time sign-ups Yes — encrypted Until you delete it
Inbox password Password for the disposable email account Yes — AES encrypted Until you delete it
One-time code (OTP) Verification code received in inbox No — memory only Not stored
Website domain Match correct credentials to current site No Not stored
Device fingerprint (Visitor ID) Fraud prevention and rate limiting Yes — opaque hash Until account deletion
IP address Rate limiting and abuse prevention Yes — short term Up to 24 hours
Supabase User ID (UUID) Internal account identifier Yes Until account deletion

We do not collect your real name, real email address, location, payment information, contacts, or any browsing history beyond the active tab's domain.

2. How We Use Your Data

We do not use any data for advertising, behavioural analytics, profiling, or any purpose not described here. We never sell, rent, or trade your data.

3. Security

Encryption

Inbox passwords are AES-encrypted client-side before being sent to our servers. Only ciphertext is stored — we cannot retrieve your plaintext password.

Transport

All communications between the extension, our Cloudflare Worker, and Supabase use HTTPS/TLS.

OTPs never stored

One-time codes are processed in memory only and discarded immediately after being displayed to you.

Admin-protected metadata

Your device fingerprint (Visitor ID) is stored in a field that only our backend can write to using an admin key. You cannot modify it from the extension.

Rate limiting

Inbox creation is limited to 4 per site per hour and 10 globally per hour, enforced via Upstash Redis. These limits survive account deletion since they are stored independently of your account records.

4. Third-Party Services

Service Role Data Received Region
Cloudflare Email Routing Receives emails to @signdup.net addresses Email content (max 1 hour) Global edge
Cloudflare Worker + KV Backend API, temporary email storage Auth tokens, inbox addresses, emails, IP addresses Global edge
Supabase Authentication and encrypted credential storage User ID, encrypted email, encrypted password, Visitor ID EU region
Upstash Redis Rate limiting IP address, request counts (auto-expires in 24h) Global
FingerprintJS (open source) Client-side device fingerprinting Runs in browser only — no external API calls Client only

None of these providers use your data for advertising. Each processes only what is necessary for their specific role.

5. Retention and Deletion

When you delete an inbox or account, records are immediately removed from Supabase. Cloudflare KV entries expire automatically within 1 hour.

6. Your Rights

EU users may also file a complaint with their local data protection authority under GDPR.

7. Cookies and Local Storage

SigndUp does not use tracking cookies. We use Chrome's storage.local API to save extension preferences, session information, and the active inbox locally on your device. This data is cleared when you uninstall the extension. No analytics or tracking cookies are used.

8. Abuse and Legal Use

SigndUp is intended for lawful personal use only. The following activities are strictly prohibited:

Violations may result in immediate account suspension and reporting to relevant authorities. To report abuse, email [email protected]. We investigate all credible reports promptly and cooperate with lawful law enforcement requests.

9. Grievance Redressal (India)

In compliance with India's Information Technology (Intermediary Guidelines and Digital Media Ethics Code) Rules, 2021, SigndUp has appointed a Grievance Redressal Officer:

Mr. Subham Patel
Email: [email protected]

All complaints will be acknowledged within 24 hours and resolved within 15 days.

10. Policy Updates

We may update this policy to reflect changes in our practices or applicable laws. Significant updates will be posted at www.signdup.net/privacy-policy. The "Last Updated" date at the top of this page always reflects the most recent revision.

SigndUp  ·  [email protected]  ·  [email protected]