Who is Certificate expiration for?

Certificate expiration is an open-source project built for firefox users and web developers.

Is Certificate expiration free?

Yes — Certificate expiration is open source under the Open Source license and free to use.

What platforms does Certificate expiration run on?

Certificate expiration runs on the web and embeddable surfaces.

Is Certificate expiration still maintained?

Unverified. Certificate expiration has not been re-checked since it entered the index, so there is no finding either way — and only a positive finding would say otherwise.

What projects are similar to Certificate expiration?

Similar projects tracked by PulseGate include CertiStatus Plus, Certificate Watch, and CertiSafeGuard.

Who develops Certificate expiration?

Certificate expiration is developed by johansigfrids.

How long has Certificate expiration been around?

Certificate expiration first shipped in 2020.

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Certificate expiration

Name: Certificate expiration
Author: johansigfrids

github.comBrowser DevTools & extensions

Certificate expiration is an open-source Firefox extension that displays the number of days remaining until a website's TLS certificate expires. It helps Firefox users and developers quickly monitor certificate validity while browsing.

Open SourceWebEmbeddable

Visit github.com

Overview

4 features

Certificate expiration sits in PulseGate's Browser DevTools & extensions category. It focuses on checking website certificate expiration dates without manually inspecting certificate details. Certificate expiration is an open-source project aimed at firefox users and web developers. The project is open source (Open Source). It runs on the web and embeddable surfaces.

johansigfrids builds and maintains Certificate expiration, and it first shipped in 2020. Among its 4 catalogued features are expiration countdown, certificate inspection, and firefox integration.

Summary written by a language model from the project’s public pages.

Expiration countdown
Certificate inspection
Firefox integration
TLS monitoring

Built with & integrations

Runs on

BrowserEmbeddable

Trust & compliance

License

Open Source

Verified signals

HTTPSPrivacy Policy Terms of ServiceOpen SourceFree tierStore-verified publisher

Legal

Indexing history

What PulseGate has recorded for this listing

Indexed11 Sep · 12:38 UTC
Certificate expiration verified via Firefox Add-ons
Source: Firefox Add-ons · Open

Frequently asked questions about Certificate expiration

What is Certificate expiration?: Certificate expiration focuses on checking website certificate expiration dates without manually inspecting certificate details. It is catalogued under Browser DevTools & extensions on PulseGate.
Who is Certificate expiration for?: Certificate expiration is an open-source project built for firefox users and web developers.
Is Certificate expiration free?: Yes — Certificate expiration is open source under the Open Source license and free to use.
What platforms does Certificate expiration run on?: Certificate expiration runs on the web and embeddable surfaces.
Is Certificate expiration still maintained?: Unverified. Certificate expiration has not been re-checked since it entered the index, so there is no finding either way — and only a positive finding would say otherwise.
What projects are similar to Certificate expiration?: Similar projects tracked by PulseGate include CertiStatus Plus, Certificate Watch, and CertiSafeGuard.CertiStatus Plus Certificate Watch CertiSafeGuard
Who develops Certificate expiration?: Certificate expiration is developed by johansigfrids.
How long has Certificate expiration been around?: Certificate expiration first shipped in 2020.

At a glance

Pricing: Open Source
Platforms: Web
Languages: English
License: Open Source
First seen: 11 Sep 2026
Built for: Firefox users and web developers
Model: Open source
Solves: Checking website certificate expiration dates without manually inspecting certificate details.

Registered as

Firefox Add-ons: certificate-expiration

Developer

johansigfrids

Index record

Indexed: 11 Sep 2026
Lifecycle: Alive
First seen: Sep 2026
Last seen: 11 Sep 2026

Identity audit (13)

Slug: certificate-expiration-github-com
Lifecycle state recorded: 11 Sep 2026
Verification state: Indexed for public listing
Listing state: Listed: yes
Index status: Included in index
Latest evidence snapshot: 11 Sep 2026
Timeline basis: Indexed-at chronology (no inferred launch/funding milestones).
Name from: Written by a language model from the project's public pages.
Category from: Assigned by a language model.
Summary from: Written by a language model from public pages.
Languages from: Detected by a language model, checked against the page's own declaration.
Last updated: 11 Sep 2026
Canonical URL: https://github.com/johansigfrids/expirator

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