Real User Monitoring for ecommerce
Your load timedecides whetherthey buy.
fastmon measures your store's load time on real customers' devices and networks. For Shopware, Shopify, Magento and any other website. In the Deloitte/Google study, 0.1 seconds less load time went along with 8.4% more retail conversions.
Deloitte/Google, Milliseconds Make Millions, 2020. 37 brands, over 30 million sessions. An observed correlation, not a promised outcome.
Why it pays off
Performance is revenue.
Slow pages lose customers before your conversion tracking even notices them. fastmon measures the Core Web Vitals of your real visitors and shows what every tenth of a second of load time is worth in revenue.
- Google ranks by real Core Web Vitals (CrUX), not lab scores
- p75 instead of averages: you see the visitors who actually suffer
- What every tenth of a second costs you, modelled with your own numbers
The product
One platform. Sixteen instruments.
Five areas, one script, the same beacons. The full list of all sixteen is further down this page.
- Core Web Vitalsp75 · 7d
LCP (p75)
0.44sBesuchererlebnis
90%gut
Gut 90%VB 4%Schlecht 6%INP56ms
CLS0.00
TTFB0.18s
FCP0.28s
Page Load0.9s
Fehlerrate0.00%
Core Web Vitals, errors and network timing from every real visit, evaluated at the p75 against Google's thresholds.
More on Real User Monitoring - LighthouseDesktop · alle 24h82Performance96Barrierefreiheit100Best Practices92SEO
Metriken
First Contentful Paint0.9 sLargest Contentful Paint1.8 sTotal Blocking Time120 msCumulative Layout Shift0.01Potenziale
Render-blocking Ressourcen entfernen50 ms sparenUngenutztes JavaScript reduzieren250 ms sparenBild-Auslieferung verbessern51 kB sparenScheduled Lighthouse audits for desktop and mobile every 24 hours, TTFB checks every 5 minutes. Lab and field side by side.
More on Synthetic Monitoring - Aktuelle Besucher
385in den letzten 5 Minuten
Top-Quellen
Direkt1.2MGoogle198.6KInstagram17.0KYouTube10.1KLive visitors in the last five minutes, sources, campaigns, UTM and ad click IDs. One less tool in your stack.
More on Analytics - fastmon AIBetaWie hat sich LCP in den letzten 7 Tagen entwickelt?
lcp_p75 (ms) · 7d
2.8002.1001.400700013.14.15.16.17.18.19.20.LCP p75 lag meist im gut-Bereich (136 bis 382 ms), mit einem Ausreißer am 19.07. (2.681 ms). Ursache lohnt einen Blick.
Ask about a test or an error in plain language and get a grounded answer. No query building, no dashboard hunting.
More on fastmon AI - Datenpfad100 % EU01IP + User-Agent
Besucher
Browser-Beacon
02→ Ländercode (DE)Edge (Falkenstein)
IP verworfen, < 1 s
03keine rohe IPBackend EU
Hetzner, Deutschland
Kein CloudflareKein AWSKein GCPKein US-AnbieterIP address and User-Agent are removed at the edge, before any application code sees them. No Cloudflare, no AWS, no GCP: the entire data path stays in the EU.
More on EU & privacy
New to this?
LCP, FCP, TTFB:just buzzwords to you?
No problem. On the blog we explain every metric in plain language: what it measures, why Google cares and how you improve it.
The index
Everything fastmon measures
- 01Core Web VitalsLCP, INP, CLS from real users: the metrics Google ranks you by.
- 02Web analyticsLive visitors, pages, sources, campaigns and UTM attribution included.
- 03Error trackingJavaScript errors with type, frequency and origin. From production.
- 04Network waterfallDNS, TCP, TLS, server, transfer: where the time actually goes.
- 05Sessions & Visitor ExplorerIndividual visits with per-page performance, duration and device context.
- 06Geo & devicesTraffic and Web Vitals by country, browser, device, connection.
- 07Performance alertsThreshold and regression rules, routed to email, Slack, Discord or webhook.
- 08Release trackingDeploys marked on charts: regressions get a timestamp.
- 09ExplorerAd-hoc analysis, p50 to p99, filter and group without SQL.
- 10Ask about a testNewAsk about a test or an error in plain language and get a grounded answer.
- 11Synthetic monitoringBetaLighthouse every 24 h and TTFB checks every 5 minutes, next to your field data.
- 12Server-TimingBackend phases like database, cache and render in every real request.
- 13Cache monitoringBrowser, CDN and origin layers, bfcache hit rates, resources by type.
- 14API & fetch monitoringEvery fetch and XHR call: slow requests, failures and tail latency.
- 15REST APIFull access with token auth and OpenAPI schema.
- 16Teams & rolesMulti-org, owner and member roles, partner clients for agencies.
For developers
Live before your coffee is done
One script tag, no build step, no configuration.
<script defer src="…/f26b….js"></script>→ 204 No Content ✓Network
204 No Content ✓
1erster Besucher
Works with any stack
and anywhere else you can add a script tag.
Designed inside the GDPR. Not retrofitted to it.
That is the difference between a monitoring tool from the EU and one with an EU region. Here is the data sheet: the honest version, footnote included.
* In Minimal and Standard mode fastmon sets no cookie and stores nothing on the device; what it reads are status values the browser generates at runtime. Full mode writes an identifier, and there consent under § 25 TDDDG is required. Assessing this is the responsibility of the respective website operator embedding fastmon.
Data sheet
- Cookies
- 0*strictly storage-free: no localStorage, no sessionStorage
- IP address
- removed at the edgebefore any application code ever sees it
- Location
- country onlytwo-letter ISO code, nothing more
- Data path
- 100% EUno Cloudflare, no AWS, no GCP
- Retention
- 90 daysdefault, configurable per website
- Fingerprinting
- noneno canvas, no font enumeration
The comparison
Lighthouse, GA4, or Datadog?
Synthetic tools don't measure what users feel. Analytics tools measure traffic, not performance. Enterprise RUM like Datadog does far more and loads a ~60 KB script; list pricing is per-session and modular. fastmon sits in between, cookieless* by default and hosted in the EU.
| Capability | fastmonPerformance RUM | LighthouseSynthetic testing | GA4Traffic analytics | PlausibleWeb analytics | Datadog RUMEnterprise RUM |
|---|---|---|---|---|---|
| Real User Monitoring (field data) | ✓ Yes | No | No | No | ✓ Yes |
| Core Web Vitals (LCP, INP, CLS) | ✓ Yes | Synthetic | No | No | ✓ Yes |
| Network & resource timing | ✓ Yes | Synthetic | No | No | ✓ Yes |
| JavaScript error tracking | ✓ Yes | No | No | No | ✓ Yes |
| Geo & device breakdowns | ✓ Yes | No | ✓ Yes | ✓ Yes | ✓ Yes |
| Works without cookies* | ✓ Yes | N/A | No | ✓ Yes | No |
| EU-hosted | ✓ Yes | N/A | No | ✓ Yes | Optional |
| Entry price | from €99/mo | free | free | from $9/mo | usage-based per session |
As of 14 July 2026: list prices / documented default configuration; individual terms may differ. *: see the footnote at the end of the page.
FAQ
Frequently asked
The honest answers, including the cookie-banner question everyone else dodges. Everything else lives in the docs.
Read the docsDo I need a cookie banner for fastmon?
No, not in Minimal and Standard mode. Nothing is stored on the device, and the values that get read were not there beforehand: they come into being at the moment of the page view. Naming fastmon in your privacy policy is enough. In Full mode you do need consent, because an identifier is written into sessionStorage. This classification has been reviewed with our external data protection officer; a residual risk remains, because no court has ruled on this constellation.
The full derivation, with the statutory text and the opposing readingDoes fastmon store IP addresses?
No. The IP address is removed at the edge before any application code ever sees it. What remains is a two-letter country code. The User-Agent header is removed at the edge as well. No canvas fingerprinting, no font enumeration, no identifier that survives a domain boundary.
The full privacy pageWhere does my data live?
The entire infrastructure runs in the EU, with no US-jurisdiction provider anywhere in the data path: no Cloudflare, no AWS, no GCP. Data is retained for 90 days by default, configurable per website. A DPA is available.
Data storage in the docsHow fast can I go live?
One script tag, about five minutes from signup to first data points. Your first visitors show up in the dashboard roughly a minute after the tag is deployed. Verify it in seconds: the collector answers 204 No Content in the network tab.
Installation guideWill the script slow my site down?
The script is vanilla JS, about 40 KB compressed, loads with defer and reads the browser's native Performance APIs instead of doing work of its own. Data goes out through navigator.sendBeacon in batches across the page lifecycle, on a deliberately lean wire format.
How the pipeline worksWhat exactly does fastmon measure?
The five Web Vitals (LCP, INP, CLS, FCP, TTFB), evaluated at the p75 against Google's thresholds, plus JavaScript errors, page load time and network timing. Everything is condensed into the Experience Score: 0 to 10, graded A+ to F, from seven weighted indicators.
Metrics & thresholdsCan I see whether a deploy made things worse?
Yes. Tag releases from your CI/CD pipeline, a single curl in the deploy step, and fastmon marks them on every chart. Compare the 24 hours after a release against the 24 hours before it, in the dashboard or via API.
CI/CD release guideDo I still need Lighthouse?
Keep it for development, and let fastmon run it for you in production: Synthetic Monitoring runs scheduled Lighthouse audits (desktop and mobile) and TTFB checks every 5 minutes next to your field data, so you can compare lab against reality in one view.
Synthetic monitoring docsPlans
The full platform, from €99 a month.
One usage-based plan. Everything is included, and the price follows your volume and nothing else. Hosted in Germany.
- 1M pageviews a month, then €50 for every further million started
- Core Web Vitals, real-user monitoring and web analytics
- Full debugging, Synthetic Monitoring and fastmon AI
- One prod application included, dev and staging free
- Hosted in Germany, 100% EU data path
More volume, longer retention or a contract of your own? Enterprise on request. See all plans