Professional-grade calculators for soil volume, plant spacing, watering routines, timber value, and field coverage. Free to use, private, and built for real growing results.
80 calculators
Each one answers a single question — how much soil, how many plants, how many trees, how many hours. Everything runs in your browser, with no sign-up.
Volume of soil, compost or mulch for beds and pots — plus how many bags that is.
How many plants fit a bed at a given spacing, using square-foot gardening densities.
How much water a planting needs each week, adjusted for plant type and season.
Trees per acre for a given spacing, on square or triangular layouts.
Board-foot volume and rough timber value from trunk diameter and height.
Field capacity from implement width, ground speed and working efficiency.
Per-acre clearing cost by terrain, tree density and hire vs. DIY.
Setup and running cost for a new plot — beds, soil, plants and tools.
No calculator matches that search. Browse all 80.
Worked examples
Four of the questions people bring to this site most often, with the numbers already run. Every calculator shows its working the same way.
26.7 cu ft just under 1 cubic yard
A 4 ft × 8 ft bed is 32 sq ft. Filled 10 inches deep, that is 32 × 0.83 = 26.7 cubic feet, or 0.99 cubic yards — about 14 two-cubic-foot bags of mix.
length × width × depth ÷ 27 = cu yd
Do this for your bed
32 plants at 12 in spacing
Allowing half a spacing to each edge, 12-inch centres give 4 rows of 8 — the classic one-per-square-foot figure. Widen to 18-inch centres and the same bed holds 10.
rows × plants per row
Try your own spacing
108 trees on a 20 ft × 20 ft grid
An acre is 43,560 sq ft. Each tree on a 20 × 20 grid claims 400 sq ft, so 43,560 ÷ 400 = 108 trees. A staggered, triangular layout fits about 125 in the same acre.
43,560 ÷ (row spacing × tree spacing)
Plan your orchard
5.8 acres 12 ft implement at 5 mph
Width in feet × speed in mph ÷ 8.25 gives acres per hour at full efficiency. At a realistic 80% — turns, overlaps, refills — a 40-acre field takes about 7 hours.
(width × speed × efficiency) ÷ 8.25
Check your setup
Method
These are planning tools, so the method matters as much as the answer. Here is what sits behind each result.
One caveat worth stating plainly: a calculator works with the numbers you give it. For anything that depends on your ground in particular — drainage, fertility, a tree you intend to sell — a soil test or a local assessment beats an estimate every time.
Answers
If yours isn't here, send it over — the common ones end up on this list.
Yes. Every calculator on the site is free, with no sign-up, no trial period and nothing held back behind a paywall. The site is supported by advertising.
Multiply length by width by depth in feet, then divide by 27 for cubic yards. A 4 ft × 8 ft bed filled 10 inches deep needs 26.7 cubic feet — just under a cubic yard. The Soil Calculator does this for you and converts it into bag counts.
Open the Soil CalculatorMany do. Where a tool accepts metric, the unit sits next to the field you type into — depths in centimetres or metres, areas in square metres or hectares, volumes in litres — so you can mix units and let the calculator convert. Tools built around Imperial-only conventions, such as board-foot timber rules, stay in Imperial because converting them would misrepresent the standard.
The arithmetic is exact — accuracy depends on your measurements. For bulk materials like soil, compost and mulch, order 5 to 10 percent more than the calculated volume to allow for settling and spillage. For the cost tools, treat the output as a planning range rather than a quote, because local rates vary widely.
No. Every calculation runs in JavaScript in your own browser. Your inputs are never sent to a server, never written to a database and never tied to an account, because there are no accounts.
There is no saved-results feature, since the site does not have accounts. Your browser's print or save-as-PDF command captures the result and the working alongside it, which is usually enough to take to a garden centre.
Guides
Longer reads on the things a calculator can't settle for you — soil mixes, timing, and what to do when the numbers and the ground disagree.
Blog
If you’ve ever stood over a houseplant with a watering can in hand, wondering whether you’re about to save it
Read the guide
Blog
If you’ve typed this question into Google, you’ve probably already noticed the problem. Every article gives you a…
Read the guide
Blog
You’ve watered on schedule, picked out disease-resistant varieties, and given your plants the right amount of sun. Yet…
Read the guideAlready know what you need to work out?
Go straight to the tool. No sign-up, no email, and it will still be free next season.