Timber Calculator: Log & CFT

Rough Book

About this app

Timber Calculator is the measuring sheet and the bill book for a timber shop or saw mill.
Measure a log, see the volume straight away, and hand the customer a PDF bill with the arithmetic shown on every line. No account, no internet, nothing leaving the phone.

FAST ENTRY, BUILT FOR THE YARD
• A full-width keypad instead of the system keyboard — no input lag, no autocorrect, keys never move
• Lock the length when a whole lorry load is cut the same, and a log becomes two taps
• Species and rate are sticky, and each species carries its own default rate
• The running sheet total is always on screen; tap any saved line to correct it
• Hold backspace to clear a field; auto-advance after two decimals

EVERY MEASURE THE TRADE USES
Round logs by girth — Hoppus / quarter-girth, true volume from girth, Francon
Round logs by diameter — Huber (mid-diameter), Smalian, Newton, Brereton, small-end cylinder, JAS scale (Japan)
Log rules for board-foot yield — Doyle, Scribner, Scribner Decimal C, International quarter Jump to bottom (click) ↓ h-inch
Sawn and cut pieces — thickness x width x length, and nominal board foot
Panels and area goods — plywood, boards, flooring
Stacked and firewood — cords and steres with a solid-content factor

UNITS
Cubic metre, cft, board foot, hoppus foot, hoppus m3, cunit, cord, stere, square foot, square metre, running foot, running metre. Conversions go through exact SI constants.

TRADE ALLOWANCES
Bark deduction off the girth, girth rounding (down, nearest, nearest even, nearest half), a defect percentage off the finished volume, and a stack factor for piles.

A BILL YOU CAN HAND OVER
Letterhead, customer block with tax registration, vehicle number, a line per piece with its own arithmetic, a volume recap per unit, extra charges (taxable or not), discount by percent or amount, tax lines,total round-off, the amount in words on the lakh-crore scale where that is the convention, and a signature block. Shared straight out of the app as a PDF. Document numbers run per type per financial year, as in INV/2026-27/0001.

REGIONAL PRESETS
India (the default), Sri Lanka, Bangladesh, Nepal, Pakistan, Myanmar, Malaysia, Indonesia, United Kingdom, Ireland, Germany, France, Europe, USA, Canada, Australia, New Zealand, Japan, Brazil, South Africa,West Africa and the Gulf — plus Custom. A region sets the default method, the units, the currency and the tax model. Everything it sets stays editable, and every method stays available whatever region you pick.

FIGURES YOU CAN DEFEND
• A hoppus foot is not a cubic foot. It is 1.2732 true cubic feet, and the app never silently mixes the two.
• A log rule estimates sawn yield, not volume, so Doyle and Scribner figures are never converted to cubic metres.
• Money is held as exact decimal, never as floating point, and tax halves always add back to the full rate.
• Rounding is your choice — round each line then add, or add the exact figures then round the total. Either way the printed lines sum to the printed total.
• Every line carries its own working, such as (84in / 4)² x 12ft, so a customer can check any figure by hand.
• A saved bill never moves. Committing a piece snapshots its figures, so changing a setting later cannot alter a bill already issued.

OFFLINE AND PRIVATE
No account, no sign-in, no servers, no ads, no tracking, no analytics. The app asks for no network permission at all, and your customer list and rates stay on your phone.

A note on tax: the rates that come with a region are a starting point, not advice, and they change. The bill prints whatever rate is stored in Settings, so please check it against the rate in force for your goods.

What’s new

First release
• Measure round logs by girth or diameter
• Hoppus, Huber, Smalian, Newton, Doyle, Scribner
• cft, m³, board foot, hoppus foot
• Sawn pieces, panels, firewood stacks
• Every line prints its own working
• GST bill shared as a PDF
• Works fully offline