Grams, cups and per-meal portions of pet food from daily kcal and the food's kcal per kg or per cup, with a treat allowance.

Estimate a dog's or cat's ideal weight from current weight and a 1-9 body condition score (10% per point above 5).

Daily calories for a dog or cat from weight, species and life stage (neutered adult, weight loss, working, young).

Split a daily food amount into evenly spaced meals between a first and last feeding time, with 12-hour clock times.

Time to fill or drain a tank from its volume or round tank size and flow in gpm, with an optional outflow.

Nitrate left after partial water changes, changes needed to reach a target, and the litres or gallons per change.

Flow rate in gpm and litres per minute from a bucket test: container volume and seconds to fill, with a daily-use estimate.

Fall needed for a drain run at a given slope in inches per foot, or the slope of a measured fall, with typical code minimums.

Water velocity in feet per second from flow in gpm and pipe size, or the flow a pipe carries at a chosen velocity.

Friction pressure loss in psi (and feet of head) over a pipe run by the Hazen-Williams formula, from flow, size and C factor.

Smallest standard copper Type L or PVC Schedule 40 pipe that keeps water under a maximum velocity at your flow rate.

How much a pipe run lengthens or shortens with temperature for copper, steel, PVC, CPVC, PEX or ABS, in inches and mm.

Water held in a run of pipe in gallons and litres per foot and in total, from nominal size or inside diameter.

Bloom filter sizing: bits, bytes and hash count for n items at a false-positive rate, or the rate for a given size.

Time to brute-force a space of N bits (or N guesses) at a guesses-per-second rate: average, worst case, and presets.

Resting energy requirement (RER) in kcal/day for a dog or cat from body weight, using 70 x kg^0.75 and the linear shortcut.

Entropy bits for a random password policy, PIN or diceware passphrase from length and alphabet, with crack-time ranges.

Birthday-problem collision odds for random IDs or hash outputs, or the count of items that reaches a target probability.

CRC-32, CRC-32C, Adler-32, FNV-1/1a (32 and 64 bit) and MurmurHash3 x86_32 of text or hex bytes. Not cryptographic.

NIST SP 800-57 comparable strengths: RSA, DH, DSA, ECC and AES key sizes to security bits, hash strengths, 2030 status.