Page Publish Date Finder - Article Date & Last Modified

For AI agents that cite web pages: give it a URL, get back when the page was published and when it was last updated, each with a confidence (high / medium / low), where the date was read from, and why that one was chosen, plus every other date found on the page. When a page has no date, it says so instead of guessing.

An answer that quotes a page without its date can present a five-year-old fact as today's news. The date is usually on the page, but in a dozen different places (JSON-LD, Open Graph meta tags, <time> elements, a "Published:" or "更新日" label, the URL, the HTTP header), and the places often disagree. This Actor reads all of them in one pass and tells you which one to trust.

Input and output in one look:

{ "urls": ["https://mag.executive.itmedia.co.jp/executive/article/2609/25/2000001737/"] }

{
  "status": "ok",
  "url": "https://mag.executive.itmedia.co.jp/executive/article/2609/25/2000001737/",
  "publishedDate": "2026-09-25T10:53:03+09:00",
  "publishedConfidence": "medium",
  "publishedSource": "meta tag",
  "publishedReason": "from meta tag name=\"cxenseparse:recs:publishtime\"; agrees with <time> element, date element, visible text; differs from JSON-LD (2026-09-25T10:53:03Z); JSON-LD gives the same clock time with a different time zone (2026-09-25T10:53:03Z); this one is used because another source's time supports it",
  "publishedTimezoneKnown": true,
  "daysSincePublished": 0,
  "modifiedDate": "2026-09-25T10:53:03Z",
  "modifiedConfidence": "low",
  "sourcesFound": ["meta tag", "date element", "JSON-LD", "<time> element", "visible text", "HTTP Last-Modified"],
  "pageLanguage": "ja"
}

(Real values from a run on 2026-09-25. This Japanese news page writes Japan time with a Z in its JSON-LD; the meta tag and the server's Last-Modified show the real time zone, so the meta tag wins and the conflict is spelled out.)

What it reads

Every date found is listed in evidence with its source, field and raw text. Sources are grouped into families; when two different families point to the same day, the date is more trustworthy.

Source (publishedSource / modifiedSource)	Where on the page	Notes
JSON-LD	<script type="application/ld+json">: datePublished, dateCreated, uploadDate, dateModified	Only the nodes that describe the page itself (top level, @graph, mainEntity). Dates of other articles listed on the page (itemListElement and similar) are not counted. The node whose url/@id equals the page wins.
meta tag	article:published_time, article:modified_time, og:updated_time, citation_publication_date, DC.date.issued, dcterms.modified, parsely-pub-date, sailthru.date, pubdate, date and 30 more; also any meta name ending in published, first_published, last_updated, modified	Names that do not say which date they are (date, DC.date) are used last.
microdata	itemprop="datePublished" / dateModified / uploadDate
<time> element	<time datetime="...">	Labelled as published or updated by pubdate, itemprop or class names (published, updated, ...). Times inside comments, related-article lists, sidebars and footers are skipped. An unlabelled <time> that equals another source's update time is treated as the update date.
date element	Elements whose class or id says pubdate, post-date, entry-date, published, updated, date, ... and whose text starts with a date	For example <div class="pubdate">2026年9月25日</div>.
visible text	Labels followed by a date: Published, Posted on, Updated, Last updated, Last modified, Last reviewed or updated, This page was last edited on, Released, 公開日, 公開, 掲載日, 投稿日, 更新日, 最終更新日, 作成日, 発表日	Text inside <code> and <pre> is ignored (so the example Last-Modified: Wed, 21 Oct 2015 ... on a documentation page is not read as the page's date).
URL	/2026/09/24/, /2026/sep/24/, 2026-09-24, /20260925-...; /2026/09/ gives the month only	Weak on its own; strong as agreement.
HTTP Last-Modified	The response header	Ignored when it equals the time the server answered (within 5 minutes), or is within 1 hour of it with no time on the page to support it (what many dynamic sites and CDN caches send); httpLastModifiedIsServeTime says so.
sitemap lastmod	<lastmod> and <news:publication_date> for the page in the sitemaps listed in robots.txt	Only with checkSitemap.
Internet Archive	First successful capture in the Wayback Machine	Only with includeWayback. Returned as firstArchivedAt and publishedNoLaterThan, never as the publish date.

Date formats read: ISO 8601 (with or without time and zone), RFC 2822 (Thu, 24 Sep 2026 18:10:00 -0400), September 24, 2026, 24 Sep 2026, 28-Jun-2026, 2026/09/24 15:42, 2026年9月25日 10時53分, 令和8年9月24日, and US zone names (EDT, PST, ...). Dates later than now and years before 1991 are ignored.

How the date is chosen

1. For each family, one date is taken (the one that describes this page).
2. The publish date comes from the first family in this order: JSON-LD, meta tag, microdata, <time>, date element, visible text, URL. The last-modified date: JSON-LD, meta tag, microdata, visible text, <time>, date element, sitemap, HTTP Last-Modified.
3. If that date is contradicted by two other strong sources that agree with each other and supported by none, the majority wins (and the reason says so).
4. If two sources give the same clock time with different time zones, the one whose instant another source supports is used.
5. Confidence:
   • high: another family agrees and no strong source disagrees. "Agrees" means within 2 hours when both have a time and zone, otherwise the same date as written on the page (a URL, sitemap or HTTP date may be one day off, because those are often in UTC).
   • medium: only one strong source, or more sources agree than disagree.
   • low: only weak sources (URL, unlabelled <time>, sitemap, HTTP header), only a month, or the sources disagree.
6. A last-modified date that equals the time the server answered (within 2 minutes) is treated as generated on each load and not used.
7. Contradictions are listed in conflicts (for example, an update date earlier than the publish date, or an Internet Archive capture older than the stated publish date).

Time zones are kept as the page wrote them. 2026-08-08T01:40:17+09:00 stays in Japan time (converting it to UTC would make it look like August 7). A time with no zone is returned without a Z and publishedTimezoneKnown is false. A date without a time has publishedTimezoneKnown: null.

Measured on real pages

49 URLs collected on 2026-09-25 (news: BBC, Ars Technica, The Verge, TechCrunch, Engadget, Al Jazeera, Wired, NHK, Asahi, ITmedia, Impress, GIGAZINE; blogs: Cloudflare, GitHub, Apify, dev.to, Smashing Magazine, Martin Fowler, Simon Willison, Qiita, Zenn, Publickey; government: GOV.UK, NASA, CDC, IRS, 厚生労働省, デジタル庁; shops: IKEA, Allbirds, Gymshark, Patagonia, Apple, Steam, 価格.com, 楽天ブックス; reference: Wikipedia, MDN, arXiv, YouTube).

• Right day, every time it answered: 28 of the pages have an independent answer (the publish date in the site's own RSS/Atom feed, or a known record such as the arXiv submission date). A publish date was returned for 27 of the 28, and all 27 are the right day. The 28th (a 厚生労働省 press release) has no date anywhere in its HTML, and the row says so instead of guessing.
• Per source (pages where the source had a publish date / of those, the right day): JSON-LD 18/18, meta tag 14/14, date element 12/12, visible text 7/7, microdata 1/1, <time> 15/14, URL 7/6 (the miss is a month-only URL, /2026/09/).
• What a reader sees: in a browser, the chosen publish date appears as written on the page for 22 of 29 dated pages. Of the other 7: 2 show only a relative time ("2 hours ago", "16 years ago"), 1 showed the browser a consent wall, 3 publish dates exist only in the page's metadata (Wikipedia's article creation date, CDC's first-published date), and 1 (Qiita) shows a posted date one day later than its JSON-LD, which is why that row is low with both dates in the reason.
• Run on Apify (one run, 49 URLs, 70 seconds, 256MB): 40 pages read, 33 with a date, 7 with none (mostly shop product pages, which rarely carry a date), 9 not read (2 check pages or refusals, 1 disallowed by robots.txt, 2 robots.txt that did not answer, 2 no longer existing, 2 no answer).
• Sitemaps added a date for only 2 of 15 pages in a separate test (both already had one), which is why checkSitemap is off by default.

Input

Field	Type	Default	What it does
urls	array of strings	(empty: the example https://blog.apify.com/fixing-actors-invisible-to-agents/ is used)	Pages to date, 1 to 1,000 per run. A URL without https:// is read as https://. The same URL given twice is read and charged once.
includeWayback	boolean	false	Also ask the Internet Archive when it first saved each URL (firstArchivedAt, publishedNoLaterThan). Slower (1 to 60 seconds per URL) and charged separately, only when a capture is found.
checkSitemap	boolean	false	Also look for the page's <lastmod> in the sitemaps listed in robots.txt (at most 4 sitemap files per page).
includeEvidence	boolean	true	Return every date found in evidence. Turn off for smaller rows.
onlyChanges	boolean	false	Monitor mode: return only pages whose chosen dates changed since the last run with the same watch name.
watchName	string	(none)	Name of the remembered state for monitor mode (letters, digits, ., -, _; up to 40).
resetMonitoringState	boolean	false	Forget what this watch remembered before this run.
maxConcurrency	integer	4	Pages read in parallel (1 to 8).
requestTimeoutSecs	integer	20	Time limit per request (5 to 60 seconds).

Output

One row per URL. Main columns:

Column	Meaning
status	ok, or why there is no date: no-date-found, robots-disallowed, robots-unreachable, login-required, blocked, not-found, http-error, unreachable, unreadable, bad-input, budget-reached, no-change
publishedDate, modifiedDate	The chosen dates (ISO 8601, time zone as written on the page), or null
publishedConfidence, modifiedConfidence	high, medium or low
publishedSource, modifiedSource	Where the chosen date was read (JSON-LD, meta tag, microdata, <time> element, date element, visible text, URL, sitemap lastmod, HTTP Last-Modified)
publishedReason, modifiedReason	Which field, what agrees, what disagrees, time zone notes
publishedTimezoneKnown, modifiedTimezoneKnown	true, false (time without zone) or null (date only)
daysSincePublished, daysSinceModified	Age in days at the time of the check
publishedNoLaterThan, firstArchivedAt, firstArchiveUrl, waybackStatus	Internet Archive first capture (found, no-capture, archive-unavailable, not-requested)
sitemapLastmod, sitemapUrl	With checkSitemap
httpLastModified, httpLastModifiedIsServeTime	The header and whether it is only the time the server answered
sourcesFound	Families that had at least one usable date
evidence	Every date found: source, field, dateType (published, modified, unknown), value, raw, timezoneKnown, precision, usedFor, ignored, detail
conflicts	Contradictions and limits (for example "The Internet Archive saved this address on 2023-03-22, before the publish date the page gives")
pageTitle, pageLanguage, canonicalUrl, finalUrl, redirects, httpStatus, contentType, htmlTruncated	About the page that was read
changeType, previousPublishedDate, previousModifiedDate, previousCheckedAt, watchName	Monitor mode (first-check, new, changed, unchanged, unconfirmed)
note, checkedAt	Why a row has no date; when the page was read

What it will not do

• It does not invent a date. A page without any date comes back as no-date-found (free). An unlabelled date that is simply today's date or the current time (a clock or a "today" display in the page header) is not used unless a labelled date on the page agrees. An HTTP Last-Modified header that is only the time the page was built or cached for the request is not used.
• It respects robots.txt for every URL (RFC 9309; its own name is NeverEmptyPageDate, otherwise the * group). Disallowed URLs are not requested.
• It does not sign in, does not solve or bypass check pages (Cloudflare, DataDome, AWS WAF, ...) and does not switch to proxies to get around a refusal. Such pages come back as a free row that says why.
• It does not run page JavaScript. Dates that only appear after scripts run cannot be seen.
• It reads up to 5MB of HTML per page. Non-HTML addresses (PDF, images) are checked for a URL date and the Last-Modified header only.

Monitor mode

With onlyChanges: true and a watchName, the first run returns every page as the starting point; later runs return only pages whose chosen publish date or last-modified date changed (a change is re-read after 1.5 seconds and reported only if both reads agree). A run in which nothing changed returns one free row and charges only the run start fee.

With a watchName but without onlyChanges, every page is returned as usual and changeType tells you what happened since the last run; a page whose dates changed but differed again on the second read is returned with changeType: "unconfirmed" and is not remembered, so the next run checks it again.

Pricing

Pay per event:

• Run start (actor-start): once per run that returns at least one dated page (in monitor mode: once per run that could read and compare).
• Date found (date-found): per URL for which a publish or last-modified date was returned.
• Internet Archive capture (wayback-first-capture): per URL for which you asked the Internet Archive and it had a capture.

Rows without a date (no date on the page, robots.txt, sign-in, check page, 404, unreachable, bad input, budget) are free. If the maximum total charge you set has no room for the start fee plus one page, nothing is requested and nothing is charged.

Calling it from code

curl -X POST "https://api.apify.com/v2/acts/neverempty~page-publish-date-finder/run-sync-get-dataset-items?token=<YOUR_TOKEN>" \
  -H "Content-Type: application/json" \
  -d '{"urls":["https://arstechnica.com/health/2026/09/cdc-opens-state-ordering-for-covid-19-vaccines-after-unexplained-delay/"],"includeEvidence":false}'

Support

Found a page where the date is wrong? Open an issue in the Issues tab with the URL and the date you expected. This is an unofficial tool that reads only what the page publicly shows.