Skip to main content

免费在线工具

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
IP Address Lookup
Look up geolocation, ISP, ASN, reverse DNS, and IP format details for any public IPv4 or IPv6 address.
Used 0 timesUpdated 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 timesUpdated never
DNS Propagation Checker
Check DNS record propagation across global public resolvers. Compare answers from Google, Cloudflare, Quad9, and more.
Used 0 timesUpdated never
Subnet Calculator
Calculate IPv4 subnet details from CIDR notation or a subnet mask. Get network, broadcast, and host ranges instantly.
Used 0 timesUpdated 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 timesUpdated 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 timesUpdated never
Traceroute Tool
Trace the network path to a hostname or IP. Shows each hop, round-trip times, and whether the route completed.
Used 0 timesUpdated never
Ping Test
Ping a hostname or IP from the server. Check reachability, packet loss, and round-trip latency.
Used 0 timesUpdated never
Website Uptime Checker
Check if a website is online from the server. See HTTP status, response time, redirects, and key response headers.
Used 0 timesUpdated never
HTTP Header Checker
Inspect HTTP response headers for any URL. Review security headers, caching directives, CORS, and server metadata.
Used 0 timesUpdated never
User Agent Parser
Parse user agent strings to identify browser, engine, operating system, device type, and bot detection.
Used 0 timesUpdated never
JSON Beautifier
Beautify and explore JSON with adjustable indentation, key sorting, a collapsible tree view, and structure stats.
Used 0 timesUpdated never