Convert an IPv4 or IPv6 address between notations: RFC 5952 compressed, expanded, integer, hex, binary, reverse DNS, NAT64.

TCP MSS from an MTU for IPv4 or IPv6, effective MTU through tunnels (PPPoE, GRE, VXLAN, WireGuard) and IPv4 fragment counts.

Convert an IPv4 prefix length, netmask, wildcard or hex mask into every other form with host counts; flags bad masks.

TCP bandwidth-delay product, window size and scale factor needed, throughput limits from window and from packet loss (Mathis).

US national debt now (Debt to the Penny): total, public vs intragovernmental, growth over a year and per day.

US Treasury official quarterly reporting exchange rate for a country's currency, with effective date and prior quarters.

Average interest rate the US government pays on Treasury bills, notes, bonds and TIPS, with change from a year ago.

Latest US Treasury yield curve from 1 month to 30 years, with 2s10s and 3m10y spreads and an inverted/flat/normal verdict.

US federal interest expense on public debt: latest month, fiscal-year-to-date and split by security type.

Caffeine remaining after hours, and the time until it drops below a threshold, from a half-life you can set (default 5 hours).

Day-by-day bedtime and wake-time shift toward a new time zone, with dates and 12-hour clock times. Planning only.

Spread between two Treasury maturities (for example 2Y and 10Y) now and over recent days, with inverted/normal verdict.

Pomodoro schedule for a task total in minutes: work blocks, short breaks, a long break every N blocks, with 12-hour clock times.

Tally nightly sleep hours against a nightly need: net shortfall, short nights, average, and extra hours a night to even out.

Split a time window into equal blocks with breaks between them, with 12-hour clock times and the minutes left over.

Nap lengths (10, 20, 30, 60, 90 minutes or your own) with the wake-up clock time for each, and a bedtime gap check.

Bedtimes for a wake-up time, or wake times for a bedtime, using 90 minute cycles plus a fall-asleep allowance. Planning only.

Air changes per hour (ACH) from airflow and room volume, or the CFM needed for a target ACH.

Equivalent round diameter of a rectangular duct (same friction), or the second side that matches a round duct.

Fan affinity laws: new airflow, pressure and power after a speed change (flow ~ N, pressure ~ N^2, power ~ N^3).