UptimeRobot says it's up.
Prove you're keeping it that way.
UptimeRobot is a great uptime monitor: it tells you the moment a client site goes down. What it does not do is prove, month after month, that you are keeping the site fast, unbroken, and looked after. SiteLetter adds Lighthouse on every page, daily visual checks across all 15 pages, and a white-label report in your inbox ready to forward - the deliverable UptimeRobot was never built to produce.
Also evaluating Oh Dear or StatusCake? See those comparisons, or browse all alternatives.
Why SiteLetter treats uptime as the floor, not the deliverable
UptimeRobot tells you the moment a client site goes down. That is worth having, and its free tier allows client use per their published terms as of August 31, 2026, so it is a fine place to start. SiteLetter is built on the view that "the homepage was up" is a floor rather than a month's work: what a retainer defends is proof the site is fast, unbroken, and looked after, and producing that proof is a different product.
Stay on UptimeRobot
If your client deliverable starts and ends at "the homepage is up," UptimeRobot is a solid pick. The free tier covers basic uptime at zero cost and is cleared for client use per their published terms as of August 31, 2026; paid tiers from EUR 9/mo billed annually add 60-second checks, more monitors, and full status pages. You keep the product you already know.
See UptimeRobot pricing →Switch to SiteLetter
SiteLetter at $4.80/site a month with every monitor on covers the whole monitoring side of a care plan: Lighthouse on every monitored page, visual regression, broken assets, SSL, and a white-label weekly or monthly email report. Uptime checks the homepage every minute. A second region re-checks any failure before an alert fires, and a third breaks a tie when the two disagree. One tool, no stack to assemble.
Start free →Quick verdict
Both tools are good. The decision comes down to who you are and what you need to deliver.
Personal sites, infrastructure, or pure-uptime use cases at scale
Hobby sites, open source projects, or anyone monitoring their own infrastructure. Also: ops teams who need ping, TCP/UDP port, DNS, cron heartbeat monitors, and far more probe vantage points, with SMS, voice, or PagerDuty alerts. UptimeRobot ships those well today; SiteLetter does not ship most of them at all.
Agencies monitoring client sites
For agencies whose monthly client deliverable is more than "the homepage was up." When a deploy shifts the contact form behind a hero image, a product photo starts 404ing, or the pricing page's Lighthouse drops from 88 to 41, none of it shows up in an up/down check. SiteLetter monitors that across every page on every site once a day, and the charge is settled once a day. Pick what is worth an alert once, at agency level, and every client site inherits it.
$4.80/site a month with every monitor on covers every monitored page on the daily pass. Uptime watches the homepage every minute. Both roll into a white-label weekly or monthly client email, the report the recipient opens without logging into anything.
"Monitor anything! Uptime, SSL, ports, cron, and more in real time."
"Website monitoring for agencies, delivered by email."
UptimeRobot pricing, checked
Commercial and client use is allowed on UptimeRobot's free plan: their published terms say so as of August 31, 2026, and the late-2024 restriction of the free plan to non-commercial use was reversed. The free plan carries 50 monitors at 5-minute checks.
Past the free plan, their paid ladder is published in euros, each rung at an annual rate and a month-to-month rate.
| Plan | Price | What it covers |
|---|---|---|
| Free plan, 50 monitors | Free | 5-minute checks and a basic status page. Commercial and client use allowed. |
| Solo plan, 10 monitors | EUR 9/mo billed annually, EUR 10/mo month to month | 60-second checks and full status pages. |
| Solo plan, 50 monitors | EUR 19/mo billed annually, EUR 22/mo month to month | 60-second checks and full status pages. |
| Team plan, 100 monitors | EUR 35/mo billed annually, EUR 41/mo month to month | 30-second checks and whitelabeled status pages. |
| Scale plan, 200 monitors | EUR 65/mo billed annually, EUR 77/mo month to month | 15-second checks and whitelabeled status pages. |
| Scale plan, 500 monitors | EUR 149/mo billed annually, EUR 179/mo month to month | 15-second checks and whitelabeled status pages. |
Source: uptimerobot.com/pricing Euros, the only currency their monitor ladder is published in. Above 500 monitors they quote on request. Read from their pricing page on .
- 10 client sites with every monitor on: $48.00 a month, for up to 150 pages.
- Switch a monitor off for a site and that site costs less. See every rate.
- Prepaid credits, no subscription. If they run out, monitoring stops, and you are warned before it does.
Which is cheaper, and for what
For uptime alone, UptimeRobot is cheaper: 10 client homepages fit inside the free plan's 50 monitors at no cost.
The SiteLetter figure is for what their plans do not carry at any rung: Lighthouse on every monitored page, day-over-day visual changes and a scheduled branded client report. If uptime is the whole job, the free plan is the better buy.
What the monthly client report needs beyond uptime
UptimeRobot is excellent at what it was built for: uptime, SSL, status pages, ping, ports, crons. The items below are a mix: some are capabilities UptimeRobot's published feature documentation does not list at any tier, including their quote-only Enterprise plan, as of August 31, 2026; others follow from metering by monitor rather than by site. SiteLetter has all of them, because the monthly client report is made of them.
Lighthouse scoring on every monitored page
UptimeRobot's monitor catalogue is uptime, SSL, port, ping, DNS, and cron heartbeat. Performance scoring is not in any of them, at any rung of their published ladder. SiteLetter runs Google Lighthouse (Performance, Accessibility, SEO, Best Practices) on every monitored page across every client site, daily, and pre-warms DNS/TLS/CDN caches before each audit so the score is stable enough to ship to a client as a trend. Cold-cache Lighthouse moves run-to-run on an unchanged page, which is what makes most third-party Lighthouse data unusable for a client report.
Daily screenshots and AI-classified diffs
UptimeRobot publishes a free website change detection tool that screenshots a page hourly and emails a before/after when it spots a difference, but it sits outside the monitoring plans, is not one of the monitor types on their website-monitoring page, and the alert is a raw diff. SiteLetter takes a fresh screenshot of every monitored page every 24 hours and runs an AI classifier across each diff big enough to matter. A rotating hero, a sale banner, a date stamp gets auto-dismissed as cosmetic noise. A genuine content update lands in the next scheduled client report. A broken layout - a deploy that shifts the contact form behind a hero image, a CDN config that drops product photos, a stylesheet that 404s - is flagged in the dashboard after the next daily scan and called out in the report you forward.
Metered by site, not by URL
UptimeRobot meters by monitor and each URL is a separate monitor. On uptime alone the counts are close: SiteLetter probes one page per site, the homepage, so five client sites is five UptimeRobot monitors, half of the Solo plan's ten (EUR 9/mo billed annually, and UptimeRobot prices in euros). Run that comparison and UptimeRobot wins it. What the monitor count never buys is the rest of the monthly deliverable: Lighthouse scores, day-over-day visual diffing and a branded client report are not in the product at any tier. SiteLetter meters by site: $4.80/site a month with every monitor on covers up to 15 pages, with Lighthouse, screenshots and broken-asset checks running daily on each of them, daily SSL and domain expiry checks for the site itself, and the sitemap re-synced weekly. Uptime runs every minute on the homepage. Each monitor is switched on per site, and a site that runs fewer costs less. No per-page tax.
A report to forward, not a status page to link to
UptimeRobot's client-facing surfaces are a public status page and an account-level monthly uptime email. Going by their published feature documentation as of the verification date below, neither is a per-client branded deliverable whose sections, cadence, and recipients you control. That second shape is what SiteLetter builds: a scheduled white-label report carrying your agency logo, brand colour, and reply-to address, end to end. The finished report lands in your inbox on your cadence, you forward it, and it opens with no SiteLetter login screen and no account creation.
A builder for the client email, not the status page
UptimeRobot lets you style a status page, and their monthly uptime email is an account-level summary rather than a per-client report you can restyle or schedule per client, going by their published feature documentation as of the verification date below. SiteLetter ships a drag-and-drop builder for the scheduled email: reorder Page Scores, Uptime, Visual Changes, Renewals, and Content Health; toggle individual metrics on or off; set weekly, bi-weekly, monthly, or quarterly cadence per client. The default layout ships ready to send; the builder is there for the client who asks for a specific shape.
Setup that ends after the URL
Adding a client site to UptimeRobot is several decisions: one URL for uptime, separate SSL and domain monitors, alert rules per monitor, status page config. Adding the same client to SiteLetter is pasting one URL. The sitemap is auto-fetched, the 15 most important pages are picked by depth + sitemap priority + recency, every monitor turns on, and the report template is pre-built. Alert rules are agency-level: pick what you want to be told about once, and every client and every site inherits it, this one included. You add recipients and you are done.
To replicate this on UptimeRobot, you would need a stack
UptimeRobot covers one slice of the agency monitoring deliverable. The other slices come from separate tools that each carry their own subscription, account, and integration cost.
- 1 UptimeRobot (paid tier sized to your portfolio)Uptime, SSL, public status pages
- 2 A separate Lighthouse SaaSPer-page performance, accessibility, SEO scoring
- 3 A separate visual regression toolDaily screenshots, change classification
- 4 A custom report pipelineBranded weekly client emails (typically built in-house)
Three subscriptions, three accounts, plus the in-house glue to email a branded report on schedule. SiteLetter is one tool, $4.80/site a month with every monitor on.
Feature-by-feature comparison
The full picture, grouped by category. Some of these are wins for SiteLetter (per-page services, white-label reports). Some are wins for UptimeRobot (alert channels, infrastructure layer). The honest answer is "both."
| Feature | SiteLetter | UptimeRobot |
|---|---|---|
| Pricing model | ||
| Pricing unit | 1 site (up to 15 pages) | 1 URL = 1 monitor |
| Every monitor on | $4.80/site a month (15 pages monitored); less per site if it runs fewer of them | Cheapest paid plan: EUR 9/mo billed annually, EUR 10/mo month to month, Solo with 10 monitors. UptimeRobot prices in euros. |
| Free tier for client work | 14 days with every monitor on, 1 site | Yes - 50 monitors, 5-min checks; commercial/client use allowed per their published terms as of August 31, 2026 |
| Monitoring data retention | 2 years (730 days) for Lighthouse, screenshots, asset checks and reports, the same window for every account; raw uptime check samples roll off after 280 days, with incidents kept alongside the rest of the history | Tiered: Free 3 months / Solo 12 months / Team and Scale 24 months |
| Per-page services on a client site | ||
| Uptime checking | Homepage every 1 min from the EU, confirmed from a second region on failure; every monitored page reached daily by the scan | Each URL = 1 monitor at fixed cadence; 5 min (Free) / 60 sec (Solo) / 30 sec (Team) / 15 sec (Scale) |
| Lighthouse audits | Every monitored page, daily | Not offered |
| AI visual regression | Every monitored page, daily, classified | Change detection published as a separate free tool (hourly screenshot, before/after email, unclassified); not a monitor type inside the paid plans (checked August 21, 2026) |
| Broken asset detection | Every monitored page, daily | Not offered |
| Hostname-level services | ||
| SSL certificate expiry alerts | Yes | Yes |
| Domain expiry alerts | Yes | Yes |
| Sitemap auto-discovery | Yes (weekly sync) | No (every URL added manually) |
| Public status page | Not available | Yes (basic on free, full on paid) |
| Infrastructure monitoring | ||
| Ping (ICMP) monitor | No | Yes |
| TCP / UDP port monitor | No | Yes |
| DNS record / heartbeat (cron) monitor | No | Yes |
| Custom HTTP methods (POST/PUT for APIs) | No | Yes |
| Multi-region probes | 3 regions (EU primary + US verifier + AP tiebreaker), monitoring data stored in the EU; screenshots go to OpenAI in the US under SCCs | 4 regions (North America, Europe, Asia, Oceania) |
| Client-facing reports | ||
| Scheduled client-facing email report | Yes (weekly, bi-weekly, monthly, quarterly) | No (status pages only) |
| Per-client branding (logo, color, reply-to) | Yes | No |
| Agency branding on every report | Yes: white-label: your logo, your brand colour, your reply-to address, and your agency name as the sender, with the SiteLetter name taken off by one toggle, sent from your own domain once you verify it | Limited - "Whitelabeled status page" removes UptimeRobot branding from status pages on Team and Scale, but no branded client report is in their published docs (checked August 21, 2026) |
| Drag-and-drop report builder | Yes | No |
| Recipients view without a login | Yes (a branded email; no account for the recipient) | No |
| Channels and integrations | ||
| Alert channels | Email, Slack | 15+ channels (Email, SMS, Voice, Push, Slack, Teams, Discord, PagerDuty, Telegram, etc.) |
| Public REST API | Not available | Yes (all plans) |
| Native mobile app | No | Yes (iOS, Android) |
Sources: uptimerobot.com/advanced-features, pricing, api. Verified .
Which job are you buying for?
Comparing monitor counts flatters whoever wrote the comparison. These are the two questions that actually decide it, at 10 client sites.
For uptime alone, UptimeRobot is a complete answer
UptimeRobot's free tier carries 50 monitors, which covers ten client homepages several times over at no cost, and their terms allow commercial and client use on it. On raw uptime they also have far more vantage points than SiteLetter and go down to 30-second and 15-second intervals on paid tiers.
SiteLetter can be bought that way too, since uptime is a line item you can switch on without the rest. But uptime alone is not the job this page is about, and pretending otherwise would mean pricing around a comparison you can run yourself in a minute.
Lighthouse, visual change detection, a branded report
None of it is in the product. UptimeRobot does not run Lighthouse audits, does not do day-over-day visual change detection, and does not send a scheduled per-client report you would forward to a client. Matching the agency deliverable means adding two or three more tools on top and wiring the report yourself.
10 client sites with every monitor on, covering up to 150 monitored pages. Prepaid, nothing recurring.
UptimeRobot figures are the ones that vendor publishes, in the currency they publish them. Verified .
Where UptimeRobot genuinely wins
UptimeRobot has been around a long time and the product depth shows. If you only need uptime (no Lighthouse, no classified day-over-day visual regression, no branded client report), or you are not running an agency where monitoring is part of a client deliverable, UptimeRobot is the better fit. The wins below are real and SiteLetter does not currently match them.
A genuinely generous free tier
Fifty monitors at a 5-minute cadence, free, and explicitly cleared for commercial and client use per their published terms as of August 31, 2026. If all you need is a simple up/down alert on a handful of sites, that is hard to beat at zero cost. SiteLetter starts you with 14 days of full monitoring on one site, and has no permanent free tier.
Faster check intervals on paid tiers
UptimeRobot monitors from four regions (North America, Europe, Asia, Oceania), verifies failures from a secondary region before opening an incident, and probes as often as every 30 seconds from their Team plan up, or every 15 seconds on Scale (their published pricing, checked August 2026). SiteLetter checks the homepage every minute from the EU and re-verifies any failure from a US region before opening an incident, with an AP region breaking ties. Every other monitored page is reached once a day by the daily scan rather than probed per minute. Monitoring data is stored in the EU. Screenshots go to OpenAI in the US for visual change classification, under EU Standard Contractual Clauses. The two-region-verification pattern is similar in shape, but UptimeRobot has many more vantage points and sub-minute cadence. If you need that level of geographic granularity or 30-second resolution on production infrastructure, UptimeRobot has the advantage.
Alert channel breadth + native mobile app
Email, SMS, voice call, native iOS / Android push, Telegram, Slack, Teams, Discord, PagerDuty, Splunk On-Call, plus webhooks. SiteLetter ships email and Slack. Other alert channels and a mobile app are not available.
Infrastructure-layer monitors + public REST API
Cron heartbeats, ping (ICMP), TCP and UDP port checks, DNS record monitoring, custom HTTP methods and headers for Basic Auth and authenticated APIs - plus a public REST API on every tier. SiteLetter monitors public-facing pages only. A public API is not available.
When to pick which
Three honest scenarios.
Agencies with a portfolio of client sites
Many client sites, on any platform. Per-page coverage, white-label reports, and the recipient flow are designed for the agency job: making monitoring a deliverable clients can see. SiteLetter is one tool, $4.80/site a month with every monitor on, and the white-label report comes with every site at no separate rate.
Pure-uptime ops at scale
DevOps, SREs, and infrastructure teams running their own services. Cron heartbeats, ping/TCP/UDP, DNS records, custom HTTP methods, many more probe locations, 30-second intervals, SMS and PagerDuty paging. UptimeRobot ships these well; SiteLetter does not ship most of them.
Personal, hobby, or small + simple
Personal sites, side projects, or a few low-stakes client sites where a simple up/down alert is the whole job. UptimeRobot's free tier covers that at zero cost and allows client use per their published terms as of August 31, 2026. SiteLetter is built around the monthly client report, which is more than this job asks for.
SiteLetter vs UptimeRobot: FAQ
No. UptimeRobot briefly restricted its free plan to non-commercial use in late 2024, but it reversed that change. The current Terms of Service and Fair Use Policy state UptimeRobot is "available for any use, including commercial and business use," and the help center explicitly welcomes "freelancers and small businesses keeping a handful of client or company sites online" on the free plan. So if you remember the old ban, it no longer applies: an agency can monitor client uptime on the free tier today. The reason to look past UptimeRobot is not its terms, it is that uptime on its own does not fill a monthly client report. Source: uptimerobot.com/terms-fair-use.
Not the ones that make up a client deliverable. UptimeRobot prices in euros, and their paid tiers (Solo at EUR 9/mo billed annually for 10 monitors or EUR 19/mo billed annually for 50, Team at EUR 35/mo billed annually for 100, Scale at EUR 65/mo billed annually for 200 or EUR 149/mo billed annually for 500) buy you more monitors, faster check intervals, and full-featured status pages. What they do not add at any tier is Lighthouse audits, classified day-over-day visual regression, or a scheduled branded client report. Those are a different category of product, and covering them in one tool is the reason SiteLetter exists. SiteLetter at $4.80/site a month with every monitor on covers uptime plus all of that in one tool.
No. UptimeRobot tracks uptime and response time on each monitor but does not run Google Lighthouse audits, so there is no Performance, Accessibility, SEO, or Best-Practices score in the product. SiteLetter audits every monitored page on every site daily, with DNS/TLS/CDN cache warmup so scores are stable enough to show clients as a real trend.
Not inside the monitoring plans. UptimeRobot publishes a free website change detection tool that screenshots a page hourly and emails a before/after image when it spots a difference, but it is a standalone free tool rather than one of the monitor types on their website-monitoring page, and the email is a raw diff you triage yourself. SiteLetter screenshots every monitored page on every site daily, diffs them against the last good capture, normally yesterday's, and sends every meaningful diff to an AI classifier that labels it as noise (rotating ads or banners) which is auto-dismissed, intentional updates which are logged in your weekly report, or real breakage (missing images, layout collapse, flagged in the dashboard and called out in the report you forward).
Not in the agency-deliverable sense. UptimeRobot ships public status pages (basic on free, full-featured on paid), which are useful but are pages your client visits, not a branded report you can put in front of them. SiteLetter is built around the white-label email report flow: per-client logo, brand color, custom reply-to address, and your agency name as the sender name, plus optional agency branding that takes "SiteLetter" out of the report body. The finished report lands in your inbox on your cadence to forward, or, once you verify your own sending domain, goes to your client from your address, so your client never sees a SiteLetter login and never creates an account.
On pure uptime, no. UptimeRobot's free tier carries 50 monitors at 5-minute checks and is cleared for client use, so on uptime alone it wins at any portfolio it covers. They price in euros, and their annual ladder runs EUR 9/mo for 10 monitors, EUR 19/mo for 50, EUR 35/mo for 100, EUR 65/mo for 200 and EUR 149/mo for 500, above which they quote on request. Those are euro prices and this page does not convert them. The real difference is what each plan covers. UptimeRobot's plans cover uptime, so if uptime is the whole job it wins on price. Matching the agency feature set means adding two or three more tools on top of it, because Lighthouse on every monitored page, classified visual regression and branded client reports are not in the product. SiteLetter at 10 client sites with every monitor on is $48.00/month, covering 150 monitored pages.
Probe locations across four regions, North America, Europe, Asia and Oceania (their own enterprise page, checked August 2026) (SiteLetter triangulates from 3: EU primary + US verifier + AP tiebreaker, monitoring data stored in the EU; screenshots go to OpenAI in the US under SCCs), more alert channels (SMS, voice call, mobile push, PagerDuty, Splunk On-Call, Telegram, Discord, Microsoft Teams, Mattermost, Pushover, Pushbullet, in addition to email and Slack), 30-second monitoring intervals from the Team plan up, and 15-second on Scale, infrastructure-layer monitors (ping, TCP/UDP port, DNS records, cron heartbeats, custom HTTP methods for authenticated APIs), a public REST API on every plan including Free, and a native mobile app. If those are part of your buying criteria, UptimeRobot is the better tool today.
Per-page Google Lighthouse on every monitored page daily with DNS/TLS/CDN cache warmup (UptimeRobot is uptime + status pages, no Lighthouse audits). AI day-over-day visual regression that classifies each diff big enough to matter as noise / intentional / breakage (UptimeRobot's page-change detection is a separate free tool that emails an unclassified before/after). White-label scheduled per-client email reports with per-client logo, brand color, reply-to (UptimeRobot email is alert-only, not scheduled per-client deliverables). Sitemap auto-discovery: add a domain, SiteLetter picks the 15 most important pages and every monitor turns on for them (UptimeRobot is per-monitor manual definition).
Yes, and the SiteLetter setup is usually shorter than the original UptimeRobot one. Each SiteLetter site covers up to 15 pages automatically (sitemap-discovered and ranked by depth, sitemap priority, and recency), so a 100-monitor UptimeRobot setup packs into 7 SiteLetter sites when every site is filled to the 15-page cap, and more than that as the same pages spread across more domains. That arithmetic assumes those monitors are extra pages of domains you already cover: the collapse is per domain, not per monitor. A hundred monitors sitting on a hundred separate client homepages stays a hundred SiteLetter sites. Add each unique site once and SiteLetter handles the rest: page selection, every monitor switched on, weekly and monthly client report templates pre-built. Migrating 100 monitors does not mean re-creating 100 alert configurations: alert rules are set once at agency level and inherited by every client and every site. New accounts get 14 days of full monitoring on one site with no card, so you can validate the full experience on one client site before bringing the rest over.
Still have questions? Get in touch.
Comparison based on publicly available UptimeRobot terms, Fair Use policy, and feature documentation, last verified . Pricing was read separately from their pricing page on August 31, 2026, which is the date the tier figures on this page carry. UptimeRobot is a trademark of its respective owner, used here for identification and comparison purposes only. SiteLetter is independent and not affiliated with, sponsored by, or endorsed by UptimeRobot. For the most current UptimeRobot pricing and feature information, see uptimerobot.com.
You set up care-plan reporting once.
After that it runs without you.
SiteLetter is the kind of tool you forget you're using, until your client thanks you for the report you didn't write.
- ✓ Just add a domain. SiteLetter auto-discovers pages, starts monitoring, schedules reports. You pick your alert rules and who gets each report.
- ✓ No scripts to install. SiteLetter monitors from the outside, like a real visitor.
- ✓ Nothing recurring. No subscription, no contract. You buy credits when you want them and each site spends its own.