Last Modified Timestamp

Published in Chrome Web Store: 4/7/2025.

v1.0.2 Released: 8/1/2025.

Tired of hunting around for when a webpage was published or last updated? This Chrome extension has you covered!

The Goal: To surface the most reliable published and last modified timestamps of any webpage, even if they're not explicitly displayed. We dig deep so you don't have to!

Features

• Finds Both Published and Modified Dates: The extension doesn't just look for when a page was last changed; it also finds the original publication date, giving you a complete picture of the content's timeline.
• Intelligent Scanning: It intelligently scans the webpage, checking meta tags, structured data (JSON-LD), visible content patterns, and even HTTP headers to find the most accurate dates.
• Customizable Date/Time Format: You can choose your preferred date and time format (e.g., YYYY-MM-DD vs. MM/DD/YYYY, 24-hour vs. 12-hour clock) from the options page.
• Simple Interface: Just click the extension icon to get the timestamps. A clear overlay provides the information without being intrusive.

How It Works

We intelligently scan the webpage for both published and modified timestamps, checking various locations where a date might be hiding. Our approach follows a logical sequence, prioritizing the most reliable sources first:

1. Meta Tags: We start by looking for direct indicators in the page's meta tags. This includes standard tags like <meta name="last-modified" ...> as well as Open Graph (OG) tags like og:updated_time (for modified) and og:published_time (for published).
2. Schema.org Structured Data: Next, we analyze any Schema.org structured data (in JSON-LD or microdata format) embedded in the page. This often contains accurate datePublished and dateModified properties.
3. HTML Content Patterns: If the above checks don't yield a result, we start looking at the visible content of the page. We search for HTML5 <time> elements and common phrases or CSS classes (like .post-date or .updated) that often indicate dates.
4. HTTP Last-Modified Header: As a final fallback for the modified date, we examine the Last-Modified header sent by the web server. While this can sometimes be less precise, it can still provide a useful indication.

Configuration

You can customize the date and time format to match your preference.

1. Right-click on the extension icon in your Chrome toolbar.
2. Select "Options".
3. Choose your desired format for the date (e.g., YYYY-MM-DD, DD/MM/YYYY) and time (24-hour or 12-hour).
4. Click "Save".

To Use

Simply install the extension. When you're on a webpage and want to know the timestamps, just click the extension icon. You'll need to click the icon each time you want to check a page.

Let us know if you have any feedback or suggestions!