River Rock Calculator
Use this river rock calculator to work out how much your project needs in cubic yards, tons and bags, then see exactly what to order. Add every bed and border in one go, pick your stone size, and check the figure against the coverage charts below. Enter a price per ton and it doubles as a cost estimator.
Calculate river rock by area and depth
Square feet × depth in inches ÷ 12 ÷ 27 = cubic yards. That is the whole calculation. The reason it trips people up is that river rock is measured by volume and sold by weight, so you need one more step to get to tons.
- Measure the area in feet. Length × width for a bed or path. For a circle, measure straight across the widest point. For an odd shape, break it into rectangles and add them up, or use the irregular option and enter the square footage.
- Choose a depth in inches. Two inches for plain ground cover, 3 inches for beds, 4 inches for drainage and slopes.
- Convert. Square feet × depth in inches ÷ 12 ÷ 27 = cubic yards. Multiply cubic yards by 1.35 to get tons of typical 1–3 inch stone.
- Add about 10%. Stone settles, ground is never flat, and edges eat more than you expect.
Say you have a bed 20 ft by 8 ft and you want 3 inches of stone in it. That is 160 sq ft, so 160 × 3 ÷ 12 = 40 cubic feet, or 1.48 cubic yards. At 2,700 lb per yard you're looking at 2 tons. Add the 10% and you order 2.5.
How much river rock do I need?
One cubic yard covers 108 square feet at 3 inches deep. One ton covers about 80. At 2 inches those become 162 and 120 square feet, and at 4 inches they drop to 81 and 60.
Depth is doing all the work in those numbers. Going from 2 inches to 4 halves what a yard covers, so a bed you thought needed one delivery needs two. Settle on the depth before you price anything.
The chart below gives every common depth for 1–3 inch stone. Read across from your depth to see what a yard and a ton each cover, then sanity-check whatever the river rock coverage calculator above tells you.
| Depth | 1 cubic yard covers | 1 ton covers | Typical use |
|---|---|---|---|
| 1" | 324 sq ft | 240 sq ft | Too thin, soil shows through |
| 2" | 162 sq ft | 120 sq ft | Minimum ground cover |
| 3" | 108 sq ft | 80 sq ft | Standard planting beds |
| 4" | 81 sq ft | 60 sq ft | Drainage, slopes, dry creek beds |
For a full breakdown by area size and stone type, see river rock coverage.
River rock coverage per ton, at every depth
A ton of 1–3 inch river rock covers 120 square feet at 2 inches, 80 at 3, and 60 at 4. Bulk stone is priced by the ton, so this is the table that tells you what your money actually buys in ground covered.
Read across a row and the pattern is the one that catches people out: coverage halves as depth doubles. Going from 2 in to 4 in on the same bed is not a small adjustment, it is twice the stone and twice the bill, and on anything over a few hundred square feet it is the difference between one delivery and two.
Larger stone covers slightly less per ton than smaller stone at the same depth, because bigger pieces leave bigger gaps between them. The effect is real but modest, and it matters far less than getting the depth right in the first place.
| Tons | Cubic yards | At 2" deep | At 3" deep | At 4" deep |
|---|---|---|---|---|
| 1 | 0.74 | 120 sq ft | 80 sq ft | 60 sq ft |
| 2 | 1.48 | 240 sq ft | 160 sq ft | 120 sq ft |
| 3 | 2.22 | 360 sq ft | 240 sq ft | 180 sq ft |
| 5 | 3.7 | 600 sq ft | 400 sq ft | 300 sq ft |
| 10 | 7.41 | 1,200 sq ft | 800 sq ft | 600 sq ft |
One ton is about three-quarters of a cubic yard, so if a supplier quotes you a “yard” of stone you're getting roughly 1.35 tons. More on 1 cubic yard of river rock and how the weight changes with stone size.
Choosing your rock size: 1–3", 2" and 3–5"
Pick 1–3 inch unless you have a reason not to. It is the most widely stocked size and the cheapest per ton, and it suits most beds and paths. Size also sets how deep you have to go: bigger stone holds more air gaps, so it weighs less per yard and needs more depth to cover.
| Stone size | Weight per cubic yard | Minimum depth | Best for |
|---|---|---|---|
| 3/4"–1" (pea-size) | 2,800 lb | 2" | Paths, patios, tight ground cover |
| 1"–3" (most common) | 2,700 lb | 2" | Beds, borders, general landscaping |
| 2" | 2,700 lb | 3" | Beds and dry creek beds |
| 3"–5" | 2,500 lb | 4" | Drainage, erosion control, accent areas |
There's a reason 1–3 inch is the default. It's big enough not to scatter when you walk on it and small enough to rake level, and being the most widely stocked size it usually comes out cheapest per ton. Go up to 3–5 inch only where you want water moving through the stone, or where you need visual weight against a large wall or slope.
How deep should river rock be?
Three inches is the answer for most planting beds. Below 2 inches the soil or landscape fabric shows through as soon as the stone shifts; above 4 inches you are paying for stone nobody sees.
- 2 inches
- Decorative ground cover over fabric, where nothing will walk on it.
- 3 inches
- Standard for beds and borders. Deep enough to block light and stop most weeds germinating.
- 4 inches or more
- Slopes, dry creek beds, French drains and anywhere water runs. Also use this for 3–5 inch stone.
The rule that catches people out: your depth must be at least as deep as your stone. Spreading 3–5 inch rock 2 inches deep is physically impossible. You get a single scattered layer with gaps in it. See river rock depth and landscape fabric for the full guidance.
Do I need landscape fabric underneath?
For decorative beds, yes. Fabric stops the stone sinking into the soil and keeps most weeds down. It does nothing about seeds that blow in on top, which is why 3 inches of depth matters more than the fabric does. For drainage work, use a permeable geotextile and never plastic sheet.
River rock weight and delivery: what a pickup can safely take
A cubic yard of 1–3 inch river rock weighs about 2,700 lb dry, or 1.35 tons. Wet stone after rain runs 10–15% heavier, which matters if you're anywhere near a vehicle’s load limit.
This is where people get hurt. A half-ton pickup is rated for roughly 1,000 lb of payload. One cubic yard of river rock is more than two and a half times that. Haul it yourself and you're doing several trips with half-loads, not one trip with a full bed.
The river rock estimator above works out how many trips your quantity needs.
Bulk delivery usually comes in a single-axle dump truck carrying 5–7 tons, or a tandem carrying 12–14.
Most yards charge a flat delivery fee within a set radius and have a 1-ton minimum, which is why very small jobs often work out cheaper in bags despite the higher price per cubic foot. Full figures for weight of river rock per yard.
Bags vs bulk: when each makes sense
It takes 54 of the 0.5 cu ft bags to make one cubic yard, so bags stop making sense faster than most people expect. Under about half a ton they still win, because you skip the delivery fee and can fit them in a car. Past a ton, bulk is almost always cheaper per unit even after delivery.
Put both prices into the calculator and it finds the crossover for your own quantity rather than a generic one.
River rock cost estimate, and what moves the price
River rock typically runs $45–$130 per ton for bulk stone you collect from the yard, or $100–$250 per ton delivered once haulage is added. Bagged rock works out at roughly $4–$9 per 0.5 cu ft bag, which is $215–$485 for the equivalent of a single cubic yard.
Those ranges are wide because stone is heavy and freight dominates the price. What you actually pay comes down to how far you are from the quarry first, then color and size. White and black river rock carry a premium over natural mixed stone, and oversized 3–5 inch stone costs more per ton than 1–3 inch.
That's why the calculator asks for your price per ton instead of showing a national average. Put in a real quote, get a real total. For regional pricing and what drives the delivery fee, see the price of river rock per ton.
Types of river rock: sizes and colors, and what each is good for
The main types of river rock come down to two things — size and color. Color changes the price and, indirectly, how much you need. Darker stone shows every gap, so it wants the full 3 inches.
- Natural mixed river rock
- Whatever the riverbed gave up, mostly gray with some tan running through it. Cheapest of the four and the most widely stocked. Hides dust and leaf litter well.
- White river rock
- High contrast against dark mulch or green planting. It also shows dirt and algae, so plan on rinsing it down every year or two. Expect to pay a premium over natural stone.
- Black river rock
- Strong modern look, but it holds a lot of heat in full sun. Keep it away from anything shallow-rooted. Usually the most expensive of the three colors.
- Large river rock (3–5 inch and up)
- Accent stone, dry creek beds, and anywhere you need something that will not wash away. Sold by the ton, and above about 8 inches often by the individual stone.
A lot of river rock is sold by where it comes from rather than a plain color name. Arizona river rock runs to warm rust, gold and tan desert tones. Colorado river rock is the cooler gray, brown and earth-toned mix. Mexican beach pebble is the smooth, near-black polished stone people use around water features and modern planting. They are the same volume math as any other rock, so pick on look and local price, then size the order with the calculator above.
Color does not change the weight per cubic yard, so the quantity math is the same whichever you pick. Size does change it, and the calculator already accounts for that.
River rock calculator FAQ
How much river rock do I need?
Multiply your area in square feet by the depth in inches, divide by 12, then divide by 27 to get cubic yards. A 10 ft × 10 ft bed at 3 inches needs 0.93 cubic yards, which is about 1.25 tons. The calculator above does this for several beds at once.
How much does a ton of river rock cover?
One ton of 1–3 inch river rock covers roughly 80 square feet at 3 inches deep, 120 square feet at 2 inches, or 60 square feet at 4 inches. Larger 3–5 inch stone covers slightly more per ton because it weighs less per cubic yard.
How much river rock is in a yard?
A cubic yard is 27 cubic feet of stone and weighs about 2,700 lb, so roughly 1.35 tons. Spread 3 inches deep it covers about 108 square feet. At 2 inches it covers 162 square feet. That’s 54 of the 0.5 cu ft bags sold at garden centers.
How many yards of river rock are in a ton?
About 0.74 cubic yards per ton, based on a dry weight of 2,700 lb per cubic yard. Put the other way round, one cubic yard is roughly 1.35 tons. Suppliers usually sell bulk river rock by the ton but quote coverage by the yard, which is where most ordering mistakes start.
How much does a yard of river rock weigh?
Around 2,700 lb, or 1.35 tons, for typical 1–3 inch stone. Smaller pea-size rock packs tighter at about 2,800 lb per yard; large 3–5 inch stone holds more air gaps and drops to roughly 2,500 lb. Wet stone can weigh 10–15% more.
How deep should river rock be for landscaping?
Two inches is the minimum that hides the soil, 3 inches is standard for planting beds and suppresses weeds properly, and 4 inches suits slopes, drainage and dry creek beds. Always go at least as deep as your stone size, or single stones will sit proud and show gaps.
Is river rock sold by the ton or the yard?
Both, and it varies by supplier. Bulk stone is most often priced by the ton but delivered by the scoop, which is measured in cubic yards. Bagged rock is sold by volume in 0.5 cu ft bags. The calculator gives all three figures so you can order in whichever unit your yard uses.
How do I calculate how much river rock I need?
Length × width gives square feet. Multiply by depth in inches, divide by 12 for cubic feet, then by 27 for cubic yards. Multiply cubic yards by 1.35 to get tons. Add about 10% for settling and uneven ground so you’re not short at the end of the job.