19 free tools
Every tool, on one page.
Site diagnostics, domains and DNS, IP checks, monitoring and reference data — everything free with no signup. Every check is a real server-side probe, never a simulated or cached guess.
1. Diagnose a site
Something won't load. Start here — every probe below runs live against the real thing.
Website Uptime Checker
Is any site down right now?
You get back: Online / Issues / Unreachable verdict, HTTP code, response time in ms.
Run a check →HTTP Status Checker
Status codes, redirect chains and response headers for any URL.
You get back: Exact status code per hop, final destination, timing.
Run a check →Redirect Checker
Every 301, 302, 307 and 308 hop with the final destination.
You get back: Full hop timeline; chains over 2 hops hurt SEO — flatten them.
Run a check →API Endpoint Checker
Status, latency, redirects and content type for an exact endpoint URL.
You get back: Code + ms + content type for the full path, query strings included.
Run a check →Live Outages
Which major sites are down right now.
You get back: Measured probe results, not votes — plus what recovered.
Run a check →2. Domains, DNS, SSL & email
Names, records and certificates — the layer where most mystery outages live.
Domain Name Checker
Availability across 8 TLDs via live RDAP.
You get back: Available / taken verdict per TLD, re-checkable at the registrar.
Run a check →WHOIS Lookup
Registrar, creation and expiry dates, status codes, nameservers, DNSSEC.
You get back: Structured record summary; unregistered names link straight to registration.
Run a check →DNS Lookup
A, AAAA, NS, CNAME, MX and TXT from Google and Cloudflare side by side.
You get back: Two-resolver comparison — mismatches mean propagation in flight.
Run a check →SSL Checker
Issuer, validity window and days left from public Certificate Transparency logs.
You get back: Expiry countdown; under 21 days means renew now.
Run a check →Blacklist Check
Whether an IP is listed on Spamhaus, in plain English.
You get back: Listed / clean verdict with reasons and delisting steps.
Run a check →3. Your connection & IP
What the internet sees about you — and whether your privacy setup leaks.
What Is My IP
Your public IP, country, ISP and timezone.
You get back: One-line answer, plus a one-click deep lookup.
Run a check →IP Lookup
City, region, ISP, organization, ASN and timezone for any public IP.
You get back: Geo + network record card with an approximate-location map.
Run a check →WebRTC Leak Test
Whether your browser exposes your real IP outside the VPN tunnel.
You get back: Leak / clean verdict. Runs entirely in your browser — nothing stored.
Run a check →VPN Guide
What a VPN does and does not do, how to choose one, honest comparisons.
You get back: No-logs criteria, torrenting/streaming picks, deals when configured.
Run a check →4. Watch it for you
One-off checks don't catch 3am outages. Continuous checks do.
5. Reference & data
Slow-moving knowledge and datasets that make the tools above useful.
Live Markets
Crypto, US stocks and gold/silver snapshots with charts.
You get back: Prices + trends. Informational only — not financial advice, and never presented as such.
Run a check →Free Public APIs
A searchable directory of 2,000+ free APIs across 50+ categories.
You get back: Official docs link + one-click status check per API. Data: public-apis/public-apis, MIT.
Run a check →Guides
Evergreen explainers on HTTP codes, DNS errors, SSL failures and the is-it-down checklist.
You get back: Ten guides, each with FAQ schema and further reading.
Run a check →FAQ
Free, 404 vs down, what Online/Issues/Unreachable mean, privacy.
You get back: Six direct answers, no fluff.
Run a check →Which one do I need?
Match your symptom to the tool. No wrong answers — they all link to each other.
| If this is happening | Open this |
|---|---|
| The whole site won't load for me | Uptime Checker → |
| One page shows an error, the rest work | HTTP Status Checker → |
| A URL changed and search traffic dropped | Redirect Checker → |
| My API returns 502, 429 or a wrong content type | API Endpoint Checker → |
| A big site is down for everyone | Live Outages → |
| Email lands in spam or bounces | Blacklist Check, then DNS Lookup for SPF/DKIM TXT → |
| Browser says “not secure” | SSL Checker → |
| It works for me but not for a colleague | DNS Lookup (two resolvers side by side) → |
| I want to stop finding out from visitors | Uptime Monitoring → |
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Why these are free.
- Display-ad impressions pay for the servers. Nobody needs to click anything.
- No accounts, no paywalls on any tool above, no data sold — ever.
- Sponsored recommendations are labeled boxes with disclosures, never rankings.
Full disclosure: how we're funded →
Need one of these built for your niche?
This site is the portfolio. We build fixed-price utility sites like it — and host them fast.
Tools FAQ
Are all of these tools free?
Yes. Every tool on this page is free with no account and no paywall. Display-ad impressions pay for the servers — nobody needs to click anything.
Do I need an account anywhere?
No. Checks, lookups and guides work anonymously. Only alert emails and paid plans (monitoring Pro, domains, hosting) ask for an email — because delivery requires one.
What's the difference between the uptime checker and the status code checker?
The uptime checker answers “is it down?” with a verdict. The status code checker shows the raw mechanics: exact codes per redirect hop, headers and timing. Start with the verdict; open the codes when you need the why.
Do you store what I check?
Hostnames and results feed the public Recently Checked board; typed terms are counted in aggregate with no IPs attached. No page content, no credentials, nothing sold. Full detail in Privacy.
Can I use these tools commercially?
Yes — checking client sites, debugging deployments and embedding result links is fine. Automated bulk scraping of the tools themselves is rate-limited; contact us for higher volumes.
Where do I start if I don't know what's broken?
Run the uptime checker first. Its verdict names the failing layer (DNS, TLS, HTTP, timeout) — then follow the one tool row above that matches, or the 11-step troubleshooting checklist.
Back to the uptime checker → · Alle Tools (DE) → · Herramientas (ES) →