Direct answer: Search-backed AI answers usually reflect a website change within about 1–45 days: Perplexity and Copilot first (about 1–7 days), then ChatGPT search (about 7–21 days), Claude (about 14–30 days) and Google AI Overviews and Gemini (about 14–45 days). Answers from a model's training data take 6–18+ months. Shortlistor measures consulting firms against these windows, with the main read-out at day 30.
The timeline, surface by surface
Each AI answer surface reads the web through a different index, so the same change lands on different days. These are typical windows from the day a change is published:
- · Perplexity and Microsoft Copilot: about 1–7 days. Perplexity fetches pages live at question time with its own crawler, and says robots.txt changes reach it within about 24 hours. Copilot answers from the Bing index, and Bing says IndexNow pings and accurate sitemap dates directly affect how fast updates appear in AI answers.
- · ChatGPT search: about 7–21 days. ChatGPT search draws mainly on Bing's index plus pages crawled by OAI-SearchBot, and also on OpenAI's own cached index, where older copies can linger for 30 days or more. OpenAI says robots.txt changes take about 24 hours to reach search.
- · Google AI Overviews, AI Mode and Gemini: about 14–45 days. AI Overviews and AI Mode use the normal Googlebot crawl and Search index, and Gemini grounds answers with live Google Search. Google says recrawling takes anywhere from a few days to a few weeks, and there is no separate AI submission path.
- · Claude with web search: about 14–30 days. Claude's web search relies on the Brave Search index plus Claude-SearchBot and live Claude-User fetches. Brave has no webmaster console, sitemap submission or IndexNow, so there is no way to push a change.
- · AI model memory (training data, search off): 6–18+ months. A change only reaches a model's built-in knowledge if a training crawler (GPTBot, ClaudeBot, Google-Extended) captured it before the next data cutoff, and only once that model ships — typically 4–6 months after cutoff, sometimes more than 12. Older models stay in use for months after that, and a small site may never be picked up.
Why it takes time: crawl, index, cache, training
Crawl: a bot has to fetch the changed page. OpenAI and Perplexity apply robots.txt changes within about a day; Google says recrawling takes anywhere from a few days to a few weeks.
Index: the page has to be processed into the index the answer engine searches — Bing for ChatGPT and Copilot, Google for AI Overviews, AI Mode and Gemini, Brave for Claude, and Perplexity's own index.
Cache: some engines keep earlier copies. ChatGPT's cached index can serve pages that are a month or more old, which is why stale answers linger longest there.
Training: answers with web search turned off come from what the model learned before its training cutoff. That only changes when a newer model ships.
How to speed it up
None of these steps forces an engine to cite your firm, but each one removes a delay between publishing and being retrievable.
- · IndexNow: ping changed, new, redirected or removed URLs on every deploy. It reaches Bing (and so Copilot and ChatGPT search) within minutes to hours; Google does not use it.
- · Bing Webmaster Tools: verify the site, submit the sitemap, submit key URLs, and watch the AI Performance report for Copilot citations.
- · Google Search Console: resubmit the sitemap and request indexing for the few most important changed URLs. Repeating the request does not help.
- · Sitemap lastmod: keep it accurate — it should change when the content changes, and removed pages should leave the sitemap.
- · Allow search crawlers in robots.txt: OAI-SearchBot, ChatGPT-User, PerplexityBot, Perplexity-User, Claude-SearchBot, Claude-User, Googlebot and Bingbot.
- · Claude: submit key URLs to Brave Search, which has no console or IndexNow.
- · Serve content in the HTML (server-rendered) and show visible last-updated dates on pages you refresh.
When to re-measure
Record a baseline before you ship: the same 20–50 hiring questions your buyers ask, run on each engine with web search on. Run each question several times, because answers vary between runs, and judge trends across checks rather than single snapshots.
- · Day 1–3: Confirm crawlers fetched the changed URLs (server logs, URL Inspection in Google Search Console and Bing Webmaster Tools).
- · Day 7: Perplexity and Copilot should already reflect the change (often within days).
- · Day 14: ChatGPT search and early Google results.
- · Day 30: Main read-out: Google AI Overviews / AI Mode, Gemini and Claude.
- · Day 45–60: Confirm the change has settled, including stale copies in ChatGPT's cache.
- · Monthly: Ongoing sampling; check search-off model answers every 6 months or when a major model ships.
How reliable are these numbers?
Treat the windows as practitioner estimates, not vendor guarantees. Only the crawl figures — OpenAI and Perplexity applying robots.txt changes within about 24 hours, and Google recrawling in a few days to a few weeks — come from the vendors themselves. Do not conclude that GEO or AEO work failed before day 30–45 on Google or Claude.
FAQ
- How long does it take for ChatGPT to show website changes?
- ChatGPT search usually reflects a change in about 7–21 days, because it relies largely on Bing's index plus OpenAI's own cached index. An IndexNow ping speeds up the Bing step. Answers without web search take 6–18+ months.
- How long until Google AI Overviews update?
- Usually about 14–45 days. AI Overviews, AI Mode and Gemini use the normal Google crawl and index; Google says recrawling takes a few days to a few weeks.
- Which AI engine updates fastest?
- Perplexity, because it fetches pages live at question time, followed by Microsoft Copilot when you ping IndexNow. Claude and Google are the slowest search-backed surfaces.
- When should a consulting firm re-measure AI visibility after changing its site?
- Check crawls in the first three days, look for early movement at day 7 and 14, take the main read-out at day 30, confirm at day 45–60, then sample monthly. Shortlistor runs that cadence for consulting firms.
Sources
- OpenAI — Overview of OpenAI crawlers
- Perplexity — Perplexity crawlers
- Bing Webmaster Blog — Keeping content discoverable with sitemaps in AI-powered search (Jul 2025)
- Bing Webmaster Blog — AI Performance in Bing Webmaster Tools (Feb 2026)
- IndexNow — FAQ
- Google Search Central — AI features and your website
- Google Search Central — Ask Google to recrawl your URLs
- Google Search Central Blog — A new resource for optimizing for AI features (May 2026)
- Google AI for Developers — Grounding with Google Search
- Anthropic — Does Anthropic crawl data from the web?
- Brave Search — Submit a URL
- AEO Hunt — How AI engines choose sources (2026, practitioner estimates)
- Ryze — How often ChatGPT and Perplexity recrawl (Aug 2026)
- LLMrefs — OpenAI's cached index for ChatGPT search (Dec 2025)
- Metehan — LLM knowledge cutoff dates (Jun 2026)
- Seer Interactive — Content recency and AI visibility (Jul 2026)
Work with a GEO and AEO company
Shortlistor helps consulting firms measure AI visibility and ship the shortlist-readiness work answer engines reward.