# Deltio

> Sitemap, SEO metadata and server uptime monitoring in one dashboard. Deltio watches a website for sitemap changes, SEO metadata regressions, marketing-tag and cookie-banner changes, broken pages, and server/SSL uptime, then alerts via email and Slack.

## Main pages
- [Deltio — home](https://www.deltio.io/): product overview, features and pricing
- [Blog](https://www.deltio.io/blog/): guides and insights on SEO, sitemaps and website monitoring

## Blog articles
- [How to Fix Index Coverage Errors in Search Console (and Catch Them First)](https://www.deltio.io/blog/fix-index-coverage-errors-gsc/): How to fix Index Coverage errors in Google Search Console by cause, and how to catch the on-page changes that create them before Google reports them.
- [Duplicate Content: How to Check for It and Keep It Fixed](https://www.deltio.io/blog/duplicate-content-checker/): How to check a site for duplicate content, where the copies come from, and how to keep canonical tags correct after every deploy.
- [Website Code Change Monitoring: Catch the Deploy That Broke Your SEO](https://www.deltio.io/blog/website-code-change-monitoring/): How to monitor a website for code changes that affect SEO: head tags, headings, hreflang and marketing tags, and how to get alerted the same day.
- [Website Migration SEO Checklist: What to Monitor Before and After](https://www.deltio.io/blog/website-migration-seo-checklist/): A website migration SEO checklist for agencies: what to record before launch, what to verify on the day, and what to monitor for 30 days after.
- [White-Label Website Monitoring for Agencies](https://www.deltio.io/blog/white-label-website-monitoring-for-agencies/): White-label website monitoring for agencies: watch every client site from one account, share a status page, and catch problems before the client does.
- [Website Monitoring in Your Monthly Client Report](https://www.deltio.io/blog/website-monitoring-client-reports/): Turn website monitoring data into your monthly client SEO report: uptime, incidents caught, SEO changes and SSL deadlines. Export to CSV with Deltio.
- [Does Downtime Hurt SEO? What Really Happens to Rankings](https://www.deltio.io/blog/does-downtime-hurt-seo/): Does downtime hurt SEO? How Googlebot handles a down site, when a blip is harmless, when a long outage hurts rankings, and how to catch it fast.
- [H1 Tag Checker: How to Find Missing and Duplicate H1s](https://www.deltio.io/blog/h1-tag-checker/): Learn what an H1 tag checker looks for and how Deltio flags missing, duplicate or changed H1 tags across every page automatically.
- [Title Tag Checker: Missing, Duplicate and Truncated Titles, Caught Early](https://www.deltio.io/blog/title-tag-checker/): A title tag checker that scans every URL for missing, duplicate or truncated titles, and flags any change it finds between scans.
- [Meta Description Checker: Catch Missing, Truncated and Duplicate Tags](https://www.deltio.io/blog/meta-description-checker/): What a meta description checker catches: missing, too long, too short and duplicated tags, and how Deltio flags changes across every client site.
- [Hreflang Checker: Find and Fix Broken Tags](https://www.deltio.io/blog/hreflang-checker/): What a hreflang checker checks: return tags, language codes, x-default, canonical conflicts. See how Deltio flags every change.
- [Canonical Tag Checker: Find and Fix Broken Canonicals](https://www.deltio.io/blog/canonical-tag-checker/): A canonical tag checker that finds missing, duplicate or wrong canonicals on every URL and alerts you the moment one changes.
- [Uptime and SEO Monitoring, in One Place](https://www.deltio.io/blog/uptime-and-seo-monitoring/): Uptime and SEO monitoring combined: what uptime checks catch, what they miss (noindex, canonical, sitemap, SSL), and why one dashboard beats three tools.
- [SSL Certificate Expiry Monitoring: Stop Finding Out From a Client](https://www.deltio.io/blog/ssl-certificate-expiry-monitoring/): SSL certificate expiry monitoring: what happens when a certificate expires, why auto-renewal fails, how to check it, and how to alert across client sites.
- [Get Alerted When robots.txt Changes](https://www.deltio.io/blog/robots-txt-change-alerts/): Set up a robots.txt changed alert: which edits are dangerous, why crawl blocking is not noindex, and how to be notified the moment a rule changes.
- [Pages Removed From Your Sitemap: What to Do Next](https://www.deltio.io/blog/pages-removed-from-sitemap/): Pages removed from sitemap? Triage in 4 steps: check status codes, find the cause, judge the real SEO impact and fix it today, plus daily monitoring.
- [How to Know the Moment a Marketing Tag Disappears (GA4, GTM, Meta Pixel)](https://www.deltio.io/blog/marketing-tag-monitoring/): How a marketing tag monitoring tool catches GA4, GTM and Meta Pixel tags that disappear, change ID or stop firing, and what to do when one does.
- [How to Monitor Sitemap Changes Automatically](https://www.deltio.io/blog/how-to-monitor-sitemap-changes/): How to monitor sitemap changes: daily snapshots, diffs of added and removed URLs, lastmod shifts, and why Search Console will not alert you.
- [How to Check GA4 Is Actually Firing on Every Page](https://www.deltio.io/blog/how-to-check-ga4-is-installed/): How to check if GA4 is installed correctly: view-source, DevTools, DebugView and Realtime, plus why one page is never enough and what to monitor.
- [Domain Expiry: The Outage Nobody Sees Coming](https://www.deltio.io/blog/domain-expiry-monitoring/): Domain expiry monitoring explained: what happens when a domain lapses, how to check expiry with RDAP and WHOIS, and how to get alerted before it bites.
- [When the Cookie Banner Changes and Nobody Tells You](https://www.deltio.io/blog/cookie-banner-monitoring/): Cookie banner monitoring: why the CMP changes without warning, what breaks in GA4 and Meta Pixel, and how to check consent behaviour by hand.
- [How to Check Your robots.txt (and the Line That Deindexes a Site)](https://www.deltio.io/blog/how-to-check-robots-txt/): How to find, read and check a robots.txt file, the one line that can block a whole site from crawling, and why robots.txt changes are a silent SEO risk.
- [The Noindex Tag, Explained: What It Does and When to Use It](https://www.deltio.io/blog/noindex-tag/): A noindex tag keeps a page out of search results. What it does, where it lives (meta tag vs HTTP header), how it differs from nofollow and robots.txt, and when to use it.
- [How to Check If a Page Is Indexed on Google](https://www.deltio.io/blog/how-to-check-if-a-page-is-indexed/): How to check if a page is indexed on Google: a site search, URL Inspection, the Pages report and crawlers, why pages aren't indexed, and how to stay ahead of it.
- [XML Sitemap Best Practices (and What Silently Breaks Them)](https://www.deltio.io/blog/xml-sitemap-best-practices/): XML sitemap best practices for SEO: include only canonical indexable URLs, keep it current, respect the limits, plus the mistakes that quietly break sitemaps.
- [SEO Monitoring Tool for Agencies](https://www.deltio.io/blog/seo-monitoring-tool/): Deltio is an SEO monitoring tool for agencies. Track SEO metadata, sitemaps, uptime and SSL across every client site, with Slack alerts. 14-day trial.
- [SEO Change Alerts: Get Notified the Moment SEO Breaks](https://www.deltio.io/blog/seo-change-alerts/): SEO change alerts notify you the moment a title, canonical, noindex or sitemap changes on a client site. What to alert on and where to send it.
- [Pingdom Alternative: Deltio vs Pingdom for Agencies](https://www.deltio.io/blog/pingdom-alternative/): A Pingdom alternative that goes beyond uptime. Deltio monitors SEO, sitemaps, marketing tags and SSL across client sites, with Slack alerts. From GBP 20 a month.
- [The SEO Changes That Break Sites Silently](https://www.deltio.io/blog/silent-seo-changes/): The SEO changes that quietly cost agencies traffic aren't the dramatic ones. Data from the sites Deltio monitors shows what actually changes, and why it matters.
- [A Website Monitoring Checklist for Agencies](https://www.deltio.io/blog/website-monitoring-checklist-for-agencies/): A practical website monitoring checklist for agencies: what to watch on every client site, how often, and who to alert. Indexing, SEO, uptime, SSL and tags.
- [How to Monitor a Client's Website for Changes](https://www.deltio.io/blog/how-to-monitor-client-websites-for-changes/): How to monitor client websites for changes: what to watch, the trade-offs of each method, and how to cover a whole portfolio without living in browser tabs.
- [How to Catch a Noindex Before It Kills Your Rankings](https://www.deltio.io/blog/how-to-catch-a-noindex-in-production/): A stray noindex quietly drops pages from Google. How it happens, how to check for it, and how to get alerted the moment it appears.
- [SEO Monitoring vs SEO Audit: What's the Difference?](https://www.deltio.io/blog/seo-monitoring-vs-seo-audit/): SEO audits are a snapshot; SEO monitoring is continuous. The difference, why you need both, and how monitoring catches what audits miss.
- [Best SEO Monitoring Tools](https://www.deltio.io/blog/best-seo-monitoring-tools/): The best SEO monitoring tools compared for agencies: change detection, rankings, audits and uptime. What each does well, and how to choose.
- [What Is SEO Monitoring (and Why Agencies Need It)](https://www.deltio.io/blog/what-is-seo-monitoring/): SEO monitoring means continuously watching a site for changes that hurt search, and getting alerted before traffic drops. What it covers and why agencies need it.
- [UptimeRobot Alternative: Deltio vs UptimeRobot for Agencies](https://www.deltio.io/blog/uptimerobot-alternative/): An UptimeRobot alternative that goes beyond uptime. Deltio monitors sitemaps, SEO, marketing tags and SSL across every client site, with Slack alerts. From £20/mo.
- [Best Website Monitoring Tools for Agencies](https://www.deltio.io/blog/best-website-monitoring-tools-for-agencies/): The best website monitoring tools for agencies in 2026: uptime, SEO, sitemap, SSL and change detection compared, with the best all-in-one pick for client portfolios.
- [Visualping Alternative: Deltio vs Visualping for Agencies](https://www.deltio.io/blog/visualping-alternative/): A Visualping alternative for monitoring client sites' SEO and technical health, not just visual page changes. Sitemap, SEO, uptime, SSL and tags. From £20/mo.
- [ContentKing Alternative: Deltio vs ContentKing for Agencies](https://www.deltio.io/blog/contentking-alternative/): A lighter, agency-friendly ContentKing alternative. Deltio monitors sitemaps, SEO, uptime, SSL and marketing tags with Slack alerts. From £20/mo.
- [Little Warden Alternative: Deltio vs Little Warden for Agencies](https://www.deltio.io/blog/little-warden-alternative/): Looking for a Little Warden alternative? Deltio monitors sitemaps, SEO, uptime and SSL across every client site and alerts you on Slack. 14-day trial from £20/mo.

## Other languages
- [Blog (it)](https://www.deltio.io/it/blog/)
- [Blog (fr)](https://www.deltio.io/fr/blog/)
- [Blog (es)](https://www.deltio.io/es/blog/)
- [Blog (de)](https://www.deltio.io/de/blog/)