Free, no sign-up: Free tools for websites and servers
The checks behind Uptimecheck, one at a time. Use them as often as you like; when you want to know the moment something changes, a monitor runs the same check for you.
- Is it down? Check whether a website answers, how fast, and when its certificate expires. Open tool
- Website uptime checker Enter a URL to test it from our server in Stockholm: whether it answers, its HTTP status code, the response time and its TLS certificate. Open tool
- Cron expression explainer Paste a crontab schedule to read it in plain English and see the next times it runs on a server in your time zone or in UTC. Open tool
- SLA and uptime calculator Turn an uptime percentage into the downtime it allows per day, week, month, quarter and year, or work out the uptime a given amount of downtime leaves. Open tool
- Downtime cost calculator Work out what downtime costs per minute, hour, incident, month and year from your own revenue, team and outages, with every formula shown. Open tool
- Status update generator Fill in what is affected and get ready-to-copy messages for every stage of an incident or planned maintenance, for your status page, email, X or Slack. Open tool
- HTTP status codes What each status code means in plain English, what usually causes it, what to do about it, and whether an uptime check counts it as down. Open tool
- SSL certificate checker See whether a site’s certificate is valid, when it expires, who issued it, which names it covers and the full chain, checked from Stockholm. Open tool
- Redirect checker Enter a URL to see every redirect hop with its status code, where it ends up and whether HTTP goes to HTTPS, checked live from Stockholm. Open tool
- HTTP header checker See every response header a URL sends, which security headers are missing, how it’s cached, and where the time goes, checked live from Stockholm. Open tool
- Open port checker Test whether a TCP port on your server accepts connections from the internet, such as 22 for SSH, 443 for HTTPS or 5432 for PostgreSQL, checked live from Stockholm. Open tool
- SPF, DKIM and DMARC checker Check a domain’s SPF, DKIM and DMARC records, MTA-STS and TLS reporting in one go, with what to fix and the exact record to add. Open tool
- SPF record generator Pick the services that send email for your domain and get one valid SPF record to publish, with its DNS lookups counted against the limit of 10. Open tool
- Domain expiry checker Look up a domain’s expiry date, registrar and age from the registry’s own records (RDAP, or WHOIS where there is none). Open tool
- DNS lookup Ask for any record type and see every answer with its TTL, straight from a resolver, without a cache in between. Open tool
Downtime is obsolete.
Set up your first monitor in under a minute, or look around the live demo first.
14-day free trial · Then free on 5 monitors · No credit card