Soil Yardage Calculator

Ordering soil sounds simple until you are standing in the garden centre trying to convert the size of a flower bed into cubic yards, or guessing how many bags will fill a raised bed. The Soil Yardage Calculator does the conversion work for you. Enter the length and width of the area in feet and the depth of soil in inches, and it returns the volume in cubic feet, the volume in cubic yards for bulk orders, and the number of standard 1.5 cubic foot bags you would need.

Getting this figure right matters in both directions. Order too little and the project stalls while you fetch more, with delivery fees paid twice on bulk loads. Order too much and you are left storing surplus soil or paying to remove it. Suppliers sell bulk soil by the cubic yard and bagged soil by the cubic foot, so a tool that speaks both languages at once saves money and trips.

This guide explains the volume maths in plain terms, shows two worked examples for a garden bed and a raised bed, and covers the two judgement calls, settling and shape, that turn a raw volume into a sensible order. Tips and FAQs round out everything gardeners usually ask.

How Soil Volume Is Calculated

Soil volume follows the same rule as any rectangular space: length multiplied by width multiplied by depth. The only complication is units. Length and width are naturally measured in feet, but soil depth is planned in inches, a few inches for topping up a bed or twelve inches for a raised bed. The calculator converts the depth into feet by dividing by 12 before multiplying, so all three dimensions agree.

The result appears in cubic feet first, the unit bags are sold in. Dividing cubic feet by 27 gives cubic yards, because one cubic yard is a cube three feet on each side, and 3 times 3 times 3 is 27. Those two numbers, cubic feet and cubic yards, are the whole vocabulary of soil ordering: bags on one side, bulk deliveries on the other.

Bags Versus Bulk: Reading the Third Result

The third result converts the same volume into 1.5 cubic foot bags, the most common bag size for topsoil and compost, and rounds up to the next whole bag, because a part-used bag is still a bag you must buy. For small jobs the bag count is the shopping list. For big volumes the bag count is a warning: once a project needs dozens of bags, bulk delivery is almost always cheaper and far less lifting.

As a rough guide, one cubic yard equals eighteen 1.5 cubic foot bags. When the calculator shows a bag count heading past twenty, price a bulk yard or two before committing to bags. Conversely, for half a cubic yard or less, bags are usually the sensible choice, since bulk suppliers often charge delivery minimums that erase the saving on small loads.

How to Use the Soil Yardage Calculator

Measure the area first with a tape, length and width in feet, then decide the soil depth in inches.

1. Enter the length of the area in feet in the first field.
2. Enter the width of the area in feet in the second field.
3. Enter the depth of soil in inches in the third field: 2 to 4 inches for topping up beds, 6 to 12 inches for raised beds.
4. Click the Calculate button.
5. Read the volume in cubic feet, the volume in cubic yards, and the number of 1.5 cubic foot bags needed.
6. Add a little extra, around 10 percent, when ordering, to allow for settling, as the deep-dive section explains.

For areas that are not simple rectangles, split them into rectangular sections, calculate each one, and add the results together. The FAQs explain this in more detail.

Worked Example 1: Topping Up a 10 by 10 Foot Bed

Suppose a square flower bed measures 10 feet by 10 feet.

You want to add a 3 inch layer of fresh soil and compost.

Convert the depth to feet: 3 divided by 12 is 0.25 feet.

Multiply length by width by depth: 10 times 10 times 0.25 gives 25 cubic feet.

Convert to cubic yards: 25 divided by 27 is about 0.93 cubic yards.

Convert to bags: 25 divided by 1.5 is 16.67, rounded up to 17 bags.

So this bed needs roughly one bulk yard, or seventeen bags, whichever suits your transport and budget better.

Worked Example 2: Filling an 8 by 4 Foot Raised Bed

A typical raised bed measures 8 feet long by 4 feet wide.

Raised beds are usually filled to a depth of about 12 inches.

Twelve inches is exactly 1 foot of depth.

The volume is 8 times 4 times 1, which is 32 cubic feet.

In cubic yards that is 32 divided by 27, about 1.19 cubic yards.

In bags, 32 divided by 1.5 is 21.33, rounded up to 22 bags.

At that scale most gardeners choose a bulk delivery of about 1.25 cubic yards, allowing a little extra for settling.

Allowing for Settling and Compaction

Freshly delivered soil is loose and full of air. Once it is watered, rained on and walked around, it settles, commonly losing 10 to 15 percent of its volume in the first few weeks. A bed filled exactly to the brim with the calculated amount will sit noticeably below the brim a month later, which is why experienced gardeners order a little more than the raw calculation suggests.

The simplest habit is to calculate exactly, as this tool does, then add about 10 percent at ordering time. For the 0.93 cubic yard bed in the first example, ordering 1 full yard covers settling neatly. For bagged soil, one or two extra bags play the same role, and unopened bags keep well for the next project, so the small over-order is rarely wasted.

Bulk Versus Bagged Soil: Cost and Effort

Bulk soil is cheaper per cubic yard by a wide margin and arrives in one delivery, but it needs a driveway or hard surface for the pile, a wheelbarrow, and the muscle to move it. Bagged soil costs more per unit yet can be carried straight to the bed, stored neatly, and bought a few bags at a time. Neither is universally better; the right choice depends on volume, access and your back.

Use the calculator’s two volume figures to compare like with like. Note the cubic yards for a bulk quote and the bag count for a bagged quote, price both, and include delivery charges in the bulk figure. On small jobs under half a cubic yard, bags usually win on total cost once delivery is counted. Above a cubic yard, bulk normally wins easily, and the gap grows with every extra yard.

Getting the Most From the Soil Yardage Calculator

A good habit with the Soil Yardage Calculator is to run the same figures twice whenever a decision depends on the answer. Data entry slips are far more common than calculation errors, and a second pass with freshly typed numbers either confirms the first result or exposes the slip while it is still cheap to fix. When the two runs agree, you can act on the figure with confidence. When they disagree, the difference points straight at the field that was typed differently, and the correct answer is usually obvious once the two versions sit side by side.

It also helps to keep a small record of the calculations that matter. Note the inputs you used, the date, and the three outputs the Soil Yardage Calculator produced. Circumstances change quietly over time, and a short record lets you rerun the same calculation months later and see exactly what has moved: the inputs, the result, or both. For anyone returning to a decision, that comparison is often more valuable than the original answer, because it turns a single snapshot into a trend you can plan around.

Many people find the Soil Yardage Calculator most useful at the comparison stage rather than the first estimate. Calculate your current position, then adjust one input at a time and calculate again: a slightly different figure here, a more ambitious target there. Changing a single variable per run keeps the cause of every change clear, and a short series of runs builds a realistic picture of which lever actually moves the result and which ones barely matter at all.

Finally, remember that every calculator answers the question it is asked, using exactly the figures it is given. The Soil Yardage Calculator is precise about arithmetic, but the judgement about whether the inputs describe your real situation belongs to you. Round numbers from memory produce round, unreliable answers. Figures taken from an actual statement, measurement or record produce results you can defend, so the two minutes spent finding the real numbers is always repaid in the quality of the decision that follows.

Another worthwhile routine is to test the extremes before settling on a plan. Run the Soil Yardage Calculator once with the most optimistic figures you can justify and once with the most cautious, then look at the gap between the two results. If the decision you are making works at both extremes, it is a robust decision. If it only works at the optimistic end, the gap tells you exactly how much risk the plan carries and where a safety margin needs to be built in.

Tips for Ordering the Right Amount of Soil

1. Measure before you calculate. Paced-out estimates of bed sizes are often a foot or more out, and every error multiplies through the volume.
2. Add about 10 percent for settling. Loose soil compacts after watering; the extra keeps beds full instead of sunken.
3. Match the depth to the job. Two to four inches refreshes a bed, six inches suits new planting areas, and raised beds want eight to twelve.
4. Compare bag and bulk prices honestly. Include delivery in the bulk price and count the bags from the calculator before deciding.
5. Split odd shapes into rectangles. L-shaped and curved beds calculate cleanly as two or three rectangular sections added together.
6. Order slightly over, not under. A second small delivery costs far more than a little surplus soil, which always finds a use in a garden.
7. Check bag size at your store. This calculator uses the common 1.5 cubic foot bag; if your bags are 2 cubic feet, you will need fewer of them.

Frequently Asked Questions

1. What does the Soil Yardage Calculator work out?

From a length, a width and a depth, it calculates the soil volume in cubic feet and cubic yards.

It also converts the volume into the number of 1.5 cubic foot bags needed, rounded up to whole bags.

2. Why is depth entered in inches but length in feet?

Because that is how gardeners naturally measure: beds are sized in feet, but soil depth is planned in inches.

The calculator converts the depth into feet internally, so you never have to do the awkward conversion yourself.

3. How many cubic feet are in a cubic yard?

There are 27 cubic feet in one cubic yard, because a cubic yard is a 3 foot cube and 3 times 3 times 3 is 27.

That is the conversion the calculator uses for the bulk ordering figure.

4. How deep should soil be in a raised bed?

Most raised beds are filled 8 to 12 inches deep, which suits vegetables and flowers while keeping the soil volume manageable.

Deeper beds hold moisture better but need noticeably more soil, which the calculator will show you before you commit.

5. How much soil do I need to top up an existing bed?

A refresh layer is usually 2 to 4 inches deep.

Enter your bed’s length and width with a depth in that range and the calculator gives the modest volume such a job needs.

6. Why does the bag count round up?

Because you cannot buy two thirds of a bag at the store.

The calculator divides the volume by 1.5 cubic feet per bag and rounds up, so the count is always enough to finish the job.

7. What if my garden bed is not rectangular?

Break the shape into rectangles, calculate each part separately, and add the volumes together.

For a circular bed, use the diameter as both length and width, then take about 80 percent of the result to allow for the corners that are not really there.

8. Should I order extra soil?

Yes, around 10 percent extra is a sensible allowance for settling and compaction.

Bulk suppliers will happily round 0.93 cubic yards up to a full yard, which covers the allowance in one step.

9. Can I use this calculator for mulch or gravel?

Yes, the volume maths is identical for any loose material measured by area and depth.

Only the purchasing details differ, such as bag sizes, so check the bag volume if you switch materials.

10. How much does a cubic yard of soil weigh?

Roughly 900 to 1,200 kilograms, or about one to one and a third tons, depending on moisture and composition.

That weight is why bulk soil is delivered rather than collected in a family car, and why several smaller loads are safer if you collect it yourself.

11. What if my measurements are in metres?

Convert metres to feet by multiplying by 3.28, and centimetres of depth to inches by dividing by 2.54, then enter the converted figures.

Keeping everything in feet and inches inside the calculator avoids unit mix-ups in the volume.

12. Is one cubic yard a lot of soil?

It covers about 100 square feet at 3 inches deep, or fills a typical 8 by 4 raised bed to about 10 inches.

Visualising coverage like this makes the yardage figure much easier to sanity check.

13. Why is bagged soil so much more expensive?

You are paying for the bagging, handling and retail distribution on top of the soil itself.

For small volumes the convenience is worth it; for large volumes the calculator’s bag count shows how quickly the cost multiplies.

14. Can I use the calculator for a sloped area?

Use the average depth across the slope as the depth entry.

If the slope is strong, split the area into two sections with different depths and add their volumes, which keeps the estimate honest.

15. How accurate is the Soil Yardage Calculator?

The volume arithmetic is exact for rectangular areas with the dimensions entered.

Real-world accuracy depends on your measurements and on settling, which is why the guide recommends the 10 percent ordering allowance.

CONCLUSION

The Soil Yardage Calculator turns a calculation that is easy to postpone, and even easier to get wrong by hand, into three clear answers you can act on straight away. You now know what each input means, how the results are worked out, and how the figures behave in the two worked examples, from the straightforward cases to the ones where the obvious guess would have misled you. Keep the practical tips in mind, especially the ones about checking inputs and allowing sensible margins, and the numbers this tool gives you will stay honest. Whenever your situation changes, come back and run the Soil Yardage Calculator again with the new figures; a decision based on today’s real numbers will always serve you better than one based on last year’s assumptions.