Free Online Tools
268+ free online tools for PDF, images, SEO, developers, color, and productivity. Fast, browser-based, and private — no signup, no installs, no limits. Search above or browse by category below.
Total tools26810.8K total uses
Categories13Active categories
Most usedJSON Formatter4.1K uses
Recently addedExperiment RandomizerNewest tool
SSL Checker
Inspect TLS certificates for any public hostname — expiry, issuer, chain, cipher, and hostname match.
Used 0 times•Updated never
SSL Expiry Checker
Check when a website SSL certificate expires. See days remaining, expiry date, chain validity, and renewal recommendations.
Used 0 times•Updated never
DNS Lookup
Query public DNS records for any domain — A, AAAA, MX, TXT, NS, CNAME, SOA, SRV, CAA, and PTR.
Used 0 times•Updated never
DMARC Checker
Look up and parse DMARC DNS records for a domain. Review policy, reporting tags, and SPF alignment hints.
Used 0 times•Updated never
IP Address Lookup
Look up geolocation, ISP, ASN, reverse DNS, and IP format details for any public IPv4 or IPv6 address.
Used 0 times•Updated never
Reverse DNS Lookup
Look up PTR reverse DNS records for a public IP address. Resolve hostnames and verify forward DNS (FCrDNS) alignment.
Used 0 times•Updated never
DNS Propagation Checker
Check DNS record propagation across global public resolvers. Compare answers from Google, Cloudflare, Quad9, and more.
Used 0 times•Updated never
Subnet Calculator
Calculate IPv4 subnet details from CIDR notation or a subnet mask. Get network, broadcast, and host ranges instantly.
Used 0 times•Updated never
CIDR Calculator
Analyze CIDR blocks, convert prefix lengths to subnet masks, split networks, and check whether an IP belongs to a range.
Used 0 times•Updated never
MX Record Lookup
Look up mail exchange (MX) DNS records for a domain, sorted by priority with mail host IP resolution.
Used 0 times•Updated never
SPF Record Checker
Look up and validate SPF TXT records for a domain. Parse mechanisms, count DNS lookups, and review policy strength.
Used 0 times•Updated never
Port Scanner
Scan common TCP ports on a public host — check which services are reachable from the server.
Used 0 times•Updated never