MISSION, ARCHITECTURE & ETHOS

About CheckSSLExpiry

A fast, trustworthy, beautifully engineered internet micro-tool built to eliminate SSL/TLS certificate expiration outages across the web — 100% free, forever, with zero user accounts or passwords.

THE PROBLEM

Why We Built CheckSSLExpiry

In modern web infrastructure, an expired SSL/TLS certificate is an unmitigated operational disaster. When a certificate lapses by even a single second, browsers block all incoming visitors with full-screen interstitial security warnings (NET::ERR_CERT_DATE_INVALID), mobile apps crash due to TLS handshake failures, and payment checkouts immediately halt.

With the CA/Browser Forum shortening certificate lifespans from 5 years to 2 years, then to 398 days, and now moving toward a mandatory 45-day validity period (pioneered by Let's Encrypt and Google Chrome's "Moving Forward, Together" initiative), manual calendar reminders and spreadsheets are fundamentally obsolete.

Yet existing enterprise monitoring platforms are bloated, expensive, require complex account signups, gate basic email alerts behind paywalls, or try to upsell unrelated features. We built CheckSSLExpiry to be the definitive, hyper-focused micro-tool for developers, webmasters, and DevOps engineers: instant, precise, 100% free, and completely passwordless.

CORE ARCHITECTURE

The Zero-Login & Passwordless Ethos

We believe the modern web has too many user accounts, passwords, and security vulnerabilities. CheckSSLExpiry is engineered with a strict Zero-Login Architecture:

  • No Passwords or User Profiles: There is no /login or /signup. You never need to remember credentials or risk database credential stuffing attacks.
  • Cryptographic Token Security: All monitor enrollment, alert threshold adjustments, and domain management are controlled exclusively via single-use, high-entropy 256-bit cryptographic tokens delivered to your verified email.
  • Zero Plaintext Tokens in Storage: We never store raw management tokens on our servers. Only irreversible SHA-256 hashes are persisted in our database.
  • 1-Click Instant Data Deletion: Every email notification contains a direct 1-click unsubscribe and data purge link, fully compliant with GDPR and CCPA "Right to Be Forgotten" standards.
INFRASTRUCTURE

Edge-Native Global Infrastructure

CheckSSLExpiry is built on top of modern edge compute technologies to deliver sub-second global certificate analysis:

Cloudflare Workers Runtime

Global edge deployment across 300+ cities with sub-millisecond execution.

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Cloudflare D1 Serverless SQL

Relational SQLite persistence for verified monitors and deduplicated alert states.

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Zero-Trust SSRF Protection

Strict RFC private network blocking preventing arbitrary network proxying.

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Open Standards & Remote MCP

OpenAPI 3.1 and Model Context Protocol (MCP) server for modern AI agent integration.

PRINCIPLES

Our Non-Negotiable Guarantees

  1. Free Forever: No premium tiers, no credit cards, no trial periods, and no locked features. The only planned monetization is unobtrusive, privacy-friendly advertising.
  2. Anti-Scope-Creep: We are laser-focused on SSL/TLS validity, expiration countdowns, DNS CAA compliance, and certificate lifecycle tracking. We do not clutter the platform with generic uptime bots or intrusive vulnerability scanners.
  3. Strict Data Minimization: We never log your real-time search queries, never touch private keys, and never sell or share user email addresses with third parties.

Start Monitoring Your Domains in Seconds

Check any public website now, verify certificate health, and enroll in free advance expiry warnings.