Skip the VPS, the Docker,
the cert renewal

The software is free (MIT license), but running it is not zero-cost. You self-host it on a VPS, a home server, or a Raspberry Pi: that costs at least $5-$20/mo for a typical DigitalOcean / Hetzner droplet. Beyond hosting, you pay in ops time: patching the OS, upgrading Docker / Node, applying Kuma version upgrades, maintaining the SQLite database and disk space, renewing the dashboard TLS certificate, and running an external "watch the watcher" check so you know if the host itself goes down. Plan for 1-3 hours/month of that work. At your own billable rate, that is the honest cost comparison. Free as in software, not free as in time.

No. Uptime Kuma ships HTTP(s), TCP, Ping, DNS, Keyword, JSON Query, Websocket, Push, Steam game server, and Docker container monitors. It does not run Google Lighthouse audits with the four-score breakdown (Performance / Accessibility / SEO / Best Practices) on monitored URLs. SiteLetter runs full Lighthouse on every monitored page on every site daily with cache warmup, and the four-score breakdown ships in the weekly client report.

No. Visual regression is not part of the Uptime Kuma feature set. SiteLetter takes a daily screenshot of every monitored page and diffs it against yesterday, with AI classifying each diff as noise (rotating banners auto-dismissed), intentional update (logged in the weekly report), or real breakage (missing images, layout collapse, emailed immediately).

No. Email is one of Uptime Kuma's many alert channels for incident notifications (you get an email when a check goes down), but there is no scheduled per-client weekly or monthly report builder, no per-client logo, no branded report layout, no one-click confirm flow for new external recipients. SiteLetter is built around that flow.

Status pages and scheduled branded client emails are different deliverables. Uptime Kuma's status pages are excellent: multiple pages, custom domain mapping, badges. Your client visits a URL to see current status. SiteLetter's scheduled email report lands directly in your client's inbox on your cadence (weekly/bi-weekly/monthly/quarterly) with your agency logo, brand color, and a write-up of what changed - including Lighthouse trends and AI-classified visual changes. Status pages answer "is it up right now?"; scheduled reports answer "what happened this month and is everything healthy?"

A lot, for the right team. Dozens of notification channels (Telegram, Discord, Gotify, Pushover, Slack, SMS gateways, and more). Multiple status pages with custom domains. A wide range of monitor types including Docker containers, Steam game servers, push heartbeats, and Websocket monitors. Full data control: the database lives on your hardware. Active OSS development on one of the most-starred self-hosted projects on GitHub, with frequent releases. Zero recurring license cost. If you are comfortable self-hosting and want full control over your monitoring infrastructure, Uptime Kuma is genuinely powerful.

Managed infrastructure: we run the host, the patches, the upgrades, the TLS renewals, and the external check that watches the watcher (Uptime Kuma is self-hosted; all of that is your operational responsibility, typically 1-3 hours/month). Per-page Google Lighthouse on every monitored page daily with DNS/TLS/CDN cache warmup (Uptime Kuma does not run Lighthouse audits). AI day-over-day visual regression that classifies each diff as noise / intentional / breakage (Uptime Kuma does not screenshot pages). Branded scheduled per-client email reports with per-client logo, brand color, reply-to, and a one-click confirm flow for new external recipients (Uptime Kuma's email is incident notifications, not scheduled per-client deliverables). Sitemap auto-discovery: add a domain, SiteLetter picks the 15 most important pages and seeds monitoring rules (Uptime Kuma is per-monitor manual definition through the dashboard).

It depends on how you count the time. Software cost: Uptime Kuma is $0; SiteLetter is $5/site. VPS hosting cost: Uptime Kuma needs $5-20/mo for a small VPS regardless of monitor count; SiteLetter has zero infrastructure cost on your side. Ops time: Uptime Kuma adds 1-3 hours/month of ongoing patching, upgrades, backups, monitor-the-monitor configuration; SiteLetter adds zero. At your hourly billing rate, the time tax usually crosses the SiteLetter price within the first few client sites. The honest comparison is "do you want to manage monitoring infrastructure, or focus on client work."

Uptime Kuma runs on one host. If that host crashes, the monitoring also stops, and the alerts that would tell you it is down originate from the same host that is down, so they never fire. Self-hosted users solve this by running a second external check (commonly a cron-based ping from another VPS, or a third-party uptime monitor) that watches the Uptime Kuma instance. That is "the monitor monitoring the monitor" - extra infrastructure to maintain. SiteLetter is managed: we run the infrastructure, we monitor it, and the alert pipeline is on us rather than your team at 3am. Probes confirm any down result across 3 AWS regions before alerting (EU primary, US verifier, AP tiebreaker), so a one-off blip in any single region will not trigger a false page. We are honest about the limit: the dispatcher itself runs in eu-north-1, so a full eu-north-1 outage pauses checks until the region recovers - same trade-off any managed monitoring service makes, but at least the operational response is our problem to solve, not yours.

Yes. The migration is conceptual rather than technical: Uptime Kuma stores monitor configs in a SQLite database on your VPS; SiteLetter sites are added via the dashboard with auto-discovery of up to 15 pages per site (sitemap + link graph). A typical 100-monitor Uptime Kuma setup collapses into 7-10 SiteLetter sites because each SiteLetter site covers 15 pages automatically. The 14-day free trial includes one site so you can validate the managed experience on one client site before bringing the rest over.