Free calculator
Topsoil Calculator
Calculate topsoil volume from area and depth, then match the result to the supplier bag or bulk specification.
Open calculator →Garden project hub
Soil, compost & mulch
These materials all use litres or cubic metres, but they are not interchangeable jobs.
Use the right quantity tool
Calculators for soil, compost & mulch
Choose the right calculator for topsoil, compost, mulch, bark, raised-bed fill and container compost.
Free calculator
Compost Calculator
Estimate compost spread over beds and borders using the area, chosen depth and actual bag size.
Open calculator →Free calculator
Mulch Calculator
Calculate organic mulch volume for beds and borders from measured area and chosen depth.
Open calculator →Free calculator
Bark Calculator
Plan bark chippings or woodchip by volume, bags and an optional existing-layer top-up.
Open calculator →Free calculator
Raised Bed Soil Calculator
Calculate the growing-medium volume needed inside a raised bed, including existing fill where relevant.
Open calculator →Free calculator
Pot & Container Compost Calculator
Calculate compost for round, tapered and rectangular pots using internal dimensions.
Open calculator →Before you order
Keep the project decisions separate from the arithmetic
Choose by what the material is doing
Topsoil usually creates or restores a meaningful soil depth. Compost can be spread over beds or used as growing media in a product-specific mix. Mulch and bark sit on the surface. Raised beds and pots are fill-volume problems based on their internal dimensions.
Volume first, weight second
The space being filled has a volume. Weight depends on density, moisture and product composition, so the strongest planning workflow calculates litres or cubic metres first and only converts to weight when a supplier figure is available.
Do not hide the supplier pack
Retail bags, bulk bags and loose deliveries vary. The calculators keep pack volume editable so the result can match the actual product instead of a nickname such as “tonne bag”.
Supporting guidance
Read the guide when the difficult part is choosing the input
Practical guide
How Much Topsoil Do I Need?
Choose a sensible soil depth, understand litres versus weight and plan bags or bulk delivery without hidden assumptions.
Read guide →Practical guide
How Deep Should Mulch Be?
Separate the horticultural decision about mulch depth from the simple volume calculation.
Read guide →Practical guide
How Much Compost for Pots & Containers?
Use internal pot dimensions, taper, fill level and rootball displacement when buying compost.
Read guide →Practical guide
How to Fill a Raised Bed
Plan internal volume, finished level, drainage context and growing-medium choices before ordering fill.
Read guide →Continue the project
Useful next routes
Move to the next quantity only when it describes a genuinely different part of the job.
Raised beds & containersUse the internal dimensions when the material is filling a bed or pot.Depth & volume referenceConvert an area and layer depth into litres or cubic metres.Lawn & turfMove to topsoil or shallow topdressing in the context of a lawn project.Gravel & aggregatesUse the same area × depth idea, but add density only when weight is actually needed.