IP Addressing

Calculate IPv4 ACL wildcard masks from CIDR and dotted entries, then audit generated lines for address coverage and dangerous overlaps.

Look up an ASN or public IP to compare current routing prefixes and neighbours with registry contacts and optional PeeringDB context.

Turn IPv4 and IPv6 CIDR rows into platform-specific prefix-list syntax, with normalized networks and ordered-policy warnings.

Check CIDR allowlists for risky address breadth and service exposure, then review ownership, expiry dates and overlapping rules before approval.

Size an IPv4 DHCP scope from real pool ranges and peak demand, then test policy choices against growth and target headroom before deployment.

Compare DNS answers with and without an EDNS Client Subnet hint, then inspect answer steering, echoed scope, TTL drift, and privacy clues.

Convert one IPv4 value across dotted, integer and bit-oriented forms with special-range labels plus optional signed and byte-order checks.

Check IPv4 CIDRs and ranges for exact duplicates, containment, partial overlap, host-bit corrections, and duplicate address coverage.

Allocate IPv4 subnets in an ordered parent CIDR, with exact usable ranges and checks for VLSM fit, alignment gaps and remaining space.

Build dependency-ordered IPv4 renumbering waves with CIDR and DNS/DHCP timing checks, window-fit rules and rollback-ready runbooks.

Size and place IPv4 child subnets from host demand, with growth headroom and reservation rules that expose gaps, overflow and usable ranges.

Summarize IPv4 CIDR blocks as one cover route or an exact aggregate set, with normalization and clear warnings for addresses exposed by gaps.

Normalize one IPv6 literal into canonical compressed and expanded forms with preserved prefix and zone context plus binary and reverse-DNS views.

Calculate an IPv6 network from an address and prefix, then review canonical boundaries, child-prefix capacity and reverse DNS or EUI-64 guidance.

Plan site and LAN prefixes from an assigned IPv6 CIDR, check demand against bit capacity, and build a normalized allocation ledger.

Check a public IP, hostname or URL for approximate location and network-owner clues with optional reverse DNS and clear evidence limits.

Calculate an IPv4 subnet boundary from CIDR or a dotted mask, then check usable hosts, special-purpose ranges and reserve-adjusted capacity.

Split an IPv4 parent block into equal CIDR children and check usable hosts, gateway placement and capacity fit across the complete subnet plan.

Calculate a TCP MSS clamp from path MTU and encapsulation overhead, with IPv4 or IPv6 header budgets, floor checks and probe guidance.

Generate an IPv4 reverse DNS zone with PTR records and SOA validation plus RFC 2317 classless delegation and parent-zone CNAME guidance.

Find the IPv4 or IPv6 route that wins for a destination using longest-prefix lookup, selectable tie-break rules, and CIDR cleanup warnings.

Generate reviewed static-route commands across host and network CLIs with CIDR normalization plus priority checks and rollback-ready delete output.

Plan IPv4 child subnets from a parent CIDR, compare post-reserve host capacity, and pack ordered VLSM demands into valid boundaries.

Split an IPv4 parent block into visual CIDR leaves, rejoin aligned siblings and verify each range, usable count and complete address coverage.

Check the public IPv4 or IPv6 address visible to your browser, with ASN, network owner, approximate location, and provider coverage.

Generate a dnsmasq IPv4 DHCP scope with CIDR and pool checks plus reservations, client options and optional PXE lines for a review-ready config.