Free single-purpose web tools

Each one does one job well. No accounts, no uploads, no tracking of what you type.

Work out gallons, litres and filled weight for rectangular, cylinder, bow-front, hex and corner tanks.

Total board feet and cost for a cutlist, plus a log scale for rough logs.

Count business days between two dates, or add/subtract business days from a deadline — with US federal holidays.

Dial in the perfect coffee-to-water ratio for pour-over, French press, AeroPress, cold brew, espresso and more.

Concrete calculator for slabs, footings, round columns and stairs — cubic yards and premix bags.

Count down to any date and time, with totals in weeks, days, hours and business days — shareable by link.

Build a cron schedule with dropdowns and see it explained in plain English.

CSV to JSON converter and formatter that runs fully in your browser, plus JSON to CSV.

Solve C1V1 = C2V2, work out dilution ratios, and plan serial dilution series.

Fabric calculator for curtains, yardage for any project, and yard/metre unit conversion.

Turn an image or a couple of characters into every favicon size you need, plus a real favicon.ico.

World Handicap System index from your last 20 rounds, plus course handicap for today's round.

Overtime pay calculator with taxes: enter your hours and rate to see regular pay, OT pay, gross and estimated take-home.

Work out partial-month rent for a mid-month move-in or move-out, compared across three proration methods.

Quilt backing, binding and border yardage from your quilt top size.

Reverse characters, words, lines, or flip your text upside down and mirrored — all at once.

Solve pace, time or distance, get splits and a race-time predictor for any distance.

Type your name in a cursive signature font, or draw your own, and download it as a transparent PNG.

Baker's-percentage sourdough calculator with true hydration, recipe scaling and a levain build helper.

Count syllables per word and per line, live, with a built-in haiku (5-7-5) check.

A weekly time card calculator with lunch break deductions, overtime and pay totals.

Tire size calculator comparison: diameter, circumference, speedometer error and ride height between two tire sizes.