# uptime.rs > Free uptime monitoring: websites, URLs and TCP ports checked every minute from 6 locations (France, Serbia, Netherlands, Sweden, Switzerland, Bulgaria), with alerts, public status pages, SSL certificate and domain expiry warnings, phishing blocklist and email record checks, and cron job heartbeats. Unlimited monitors, no credit card. A monitor is down only when every location fails two checks in a row. Cloudflare challenges count as "challenged", not down. Monitor data needs an account; the tools below need nothing. ## For AI agents - [MCP server](https://uptime.rs/mcp): Model Context Protocol, streamable HTTP (POST JSON-RPC). Tools without a key: check_website, check_ssl, check_domain_expiry, ping. With "Authorization: Bearer ": list_monitors, get_monitor, monitor_checks, list_incidents, add_monitors, pause_monitor, resume_monitor. - [Agent skill](https://uptime.rs/skills/uptime-rs/SKILL.md): SKILL.md that tells an agent when and how to use uptime.rs ([zip](https://uptime.rs/skills/uptime-rs.zip)). - [OpenAPI](https://uptime.rs/openapi.json): the free tools API and the REST API. - [Docs for agents](https://uptime.rs/docs/agents) ## Free tools API (no key, 30 requests per minute per IP) - GET https://uptime.rs/api/v1/tools/website?host=example.com : is it up, status code, response time, redirects, server, Cloudflare. - GET https://uptime.rs/api/v1/tools/ssl?host=example.com : certificate issuer, names, expiry, days left, trusted. - GET https://uptime.rs/api/v1/tools/domain?host=example.com : registered, expiry date, days left, registrar (RDAP/WHOIS). - GET https://uptime.rs/api/v1/tools/ping?host=example.com&port=443 : TCP ping, min/avg/max connect time. ## Free tools (web) - [Website down checker](https://uptime.rs/tools/website-down-checker): Check if a website is down for everyone or just you: status code, response time, redirects, server and Cloudflare, checked live from our server. Free, no sign-up. - [SSL checker](https://uptime.rs/tools/ssl-checker): Check any site's SSL certificate: when it expires, days left, who issued it, which names it covers, and whether browsers trust it. Free, no sign-up. - [Domain expiry checker](https://uptime.rs/tools/domain-expiry-checker): Look up when a domain expires, how many days are left and who the registrar is, straight from the registry (RDAP or WHOIS). Works for .com, .rs, .de, .eu and more. Free. - [Ping and port checker](https://uptime.rs/tools/ping): Ping a host online and check if a port is open: four TCP connects with min, average and max time, from our server. Works where ICMP is blocked. Free, no sign-up. ## Features - [Website monitoring](https://uptime.rs/features/website-monitoring): Free website uptime monitoring: every site checked every minute from 6 locations, alerts only when it is really down, response times and 30-day uptime. Unlimited monitors. - [SSL certificate monitoring](https://uptime.rs/features/ssl-certificate-monitoring): Get an alert before an SSL certificate expires: we read the certificate of every https monitor daily and warn you 14 days, 3 days and on the day. Free, for every site. - [Domain expiry monitoring](https://uptime.rs/features/domain-expiry-monitoring): Never lose a domain to a missed renewal: daily RDAP and WHOIS checks of every monitored domain, with warnings 30 days, 7 days and on the day it expires. Free. - [Status pages](https://uptime.rs/features/status-pages): A free, hosted status page for your sites and services: live status, 60-day uptime, incident updates, scheduled maintenance, email subscribers, RSS, badges and your own domain. - [Cron job monitoring](https://uptime.rs/features/cron-job-monitoring): Know when a backup, cron job or queue worker stops running: each heartbeat monitor gets a ping URL, and you are alerted when the ping does not arrive on time. Free. - [TCP port monitoring](https://uptime.rs/features/port-monitoring): Monitor any TCP service, such as databases, mail servers, SSH or game servers: we open a connection every minute from 6 locations and alert you when it is refused or times out. - [Blocklist monitoring](https://uptime.rs/features/blocklist-monitoring): Find out when your domain lands on a phishing blocklist, and when its MX, SPF, DKIM or DMARC records break. Every monitored domain is checked daily, for free. - [Downtime alerts](https://uptime.rs/features/downtime-alerts): Get downtime alerts by email, Slack, Discord, Telegram, Microsoft Teams, Google Chat, PagerDuty, Opsgenie, Pushover, ntfy, SMS or webhook, grouped so an outage sends one message. - [Cloudflare-aware monitoring](https://uptime.rs/features/cloudflare-monitoring): Uptime monitoring for sites behind Cloudflare: challenges and "Under Attack" mode are shown as challenged, not down, and errors 52x, 530 and tunnel error 1033 are explained. - [Agencies and client reports](https://uptime.rs/features/client-reports): Monitor every client site, send monthly uptime reports with your own brand and SMTP server, and give clients access to only their own monitors. Free, unlimited monitors. - [API, MCP and AI agents](https://uptime.rs/features/ai-agents): Let AI agents check if a site is down, read SSL and domain expiry, ping hosts and manage monitors: an MCP server, an agent skill, a free tools API, a REST API and llms.txt. ## Docs - [Getting started](https://uptime.rs/docs/getting-started): Create an account, add your first monitors and get alerted when a site goes down. - [Adding monitors](https://uptime.rs/docs/monitors): Add websites, URLs, TCP ports and cron jobs, set check options, and manage, pause and troubleshoot monitors. - [Importing domains](https://uptime.rs/docs/importing): Import domains from OpenPanel, cPanel, Plesk, Cloudflare and Namecheap. - [Check locations](https://uptime.rs/docs/locations): Where checks run from, how a monitor is marked down, and which IPs to allow. - [Alerts](https://uptime.rs/docs/alerts): Email, Slack, Discord, Telegram, Teams, PagerDuty, SMS and webhook alerts, expiry warnings, weekly summaries and alert history. - [Status pages](https://uptime.rs/docs/status-pages): Public status pages: styling, custom domains, password protection, incidents, maintenance, subscribers and badges. - [Teams, branding and client reports](https://uptime.rs/docs/teams): Invite colleagues and clients with roles, send emails with your own brand and SMTP server, and email uptime reports to clients. - [Account and security](https://uptime.rs/docs/security): Two-factor authentication, passkeys, email and password changes, language, the activity log, data export and deleting your account. - [API](https://uptime.rs/docs/api): Manage monitors and read uptime, checks and incidents from your own scripts: API keys, limits and endpoints. - [AI agents and MCP](https://uptime.rs/docs/agents): Let AI agents check sites, SSL and domain expiry and manage monitors: the MCP server, the agent skill, the free tools API, OpenAPI and llms.txt. ## Optional - [Sign up](https://uptime.rs/register): free account, unlimited monitors. - Status pages: every monitored domain has a public page at .status.uptime.rs, with an uptime badge at /badge/.svg. - [Contact](https://uptime.rs/contact)