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Calculate IPv4 subnet details from CIDR notation or a subnet mask. Get network, broadcast, and host ranges instantly.

Analyze CIDR blocks, convert prefix lengths to subnet masks, split networks, and check whether an IP belongs to a range.

Look up mail exchange (MX) DNS records for a domain, sorted by priority with mail host IP resolution.

Look up and validate SPF TXT records for a domain. Parse mechanisms, count DNS lookups, and review policy strength.

Trace the network path to a hostname or IP. Shows each hop, round-trip times, and whether the route completed.

Check if a website is online from the server. See HTTP status, response time, redirects, and key response headers.

Compare two texts and highlight added, removed, and changed lines or words instantly in your browser.

Decode JSON Web Tokens to inspect the header, payload, and claims instantly in your browser — no data leaves your device.

Beautify and explore JSON with adjustable indentation, key sorting, a collapsible tree view, and structure stats.

Convert JSON to clean, indented XML with configurable root and item element names — entirely in your browser.

Convert XML into clean JSON with attribute handling, type parsing, and adjustable indentation — all in your browser.

Convert JSON into clean, readable YAML with adjustable indentation — entirely in your browser.