Gravel and Flex Base Calculator for Texas Ranch and Site Work
Enter your project dimensions
Texas is too big for one kind of dirt, but across the Blackland Prairie and much of north and central Texas the ground is expansive clay that swells and shrinks with the seasons, and from the Hill Country to the Gulf Coast one flash-flood downpour can move more rock than a month of traffic. Whatever your dirt, the gravel calculator does the same honest job: it turns length, width and depth into cubic yards, tons and cubic feet so you can order with a firm number.
The job this tool does, and the calls it leaves to you
| The calculator handles | You still decide |
|---|---|
| Volume for rectangles, circles, or up to 5 areas combined | How thick the rock needs to be for your load and soil |
| Conversion to tons using the weight of the material you pick | Whether the job needs a base and a separate top course |
| An optional 5% for compaction and spillage | How much clay or topsoil to strip before rock goes down |
| Results in yards, tons and cubic feet | Where runoff goes when a flash storm hits |
On expansive clay, those judgment calls matter. Clay that heaves in a wet spring and shrinks in August will crack a thin base, so decide depth before you trust any number. The same goes for a long ranch road. The tool will size a quarter mile of Flex Base as easily as a patio, but it can't tell which low crossing needs a thicker section or a culvert. Walk the route after a hard rain, note where water crosses or stands, and enter those stretches as their own areas with extra depth.
Four units, one pile of rock
| Unit | What it measures | How you get it |
|---|---|---|
| Square feet | Footprint on the ground | length x width |
| Cubic feet | Space the rock fills | square feet x depth in inches ÷ 12 |
| Cubic yards | Bulk volume, the way rock is sold | cubic feet ÷ 27 |
| Tons | Weight | cubic yards x material density |
The densities the calculator applies:
| Material | lb per yd³ | tons per yd³ |
|---|---|---|
| Driveway / walkway gravel | ~2,800 | 1.40 |
| Pea gravel (3/8") | ~2,800 | 1.40 |
| Crushed stone (#57, 3/4") | ~2,800 | 1.40 |
| Crusher run / road base | ~3,000 | 1.50 |
| River rock (1-3") | ~2,700 | 1.35 |
Flex Base is this site's road base product, so it runs at 1.50. The same goes for crushed limestone base, listed as Crusher Run.
Punching in your numbers
Choose a shape first. Rectangle wants length and width, Circle wants a diameter, both in feet. Multiple areas stacks up to five pieces, which is how you handle a pad plus an approach, or a drive that doglegs to the barn. Next, set depth in inches, anywhere from 0.25 to 24. Pick the material, then decide on the "add 5% extra for compaction & spillage" box. Tick it for base you'll roll. Hit calculate. You get yards, tons and cubic feet, plus an Email my quote button if you want the estimate in your inbox.
Three sample jobs
All three are hypothetical, sized to show the arithmetic.
Stock tank shoreline
Say an 80 ft stretch of bank where cattle and wave action keep cutting the edge. You want a band 3 ft wide and 6 inches deep of Texas River Rock. The math: 80 x 3 x 6 ÷ 12 = 120 cubic feet, then ÷ 27 = 4.44 yd³, then x 1.35 = 6.0 tons. Where water hits the bank hard, heavier armor is the better fit; size that on the rip rap calculator.
Construction entrance on a new build
The entrance is 50 ft long and 20 ft wide, with 8 inches of 3/4" crushed stone to keep mud off the road. The math: 50 x 20 x 8 ÷ 12 = 666.7 cubic feet, then ÷ 27 = 24.7 yd³, then x 1.40 = 34.6 tons. With the 5% box ticked, it comes to 25.9 yd³ and 36.3 tons.
Paver patio on clay
The patio is 20 x 16 ft with 6 inches of Flex Base under the pavers. The math: 20 x 16 x 6 ÷ 12 = 160 cubic feet, then ÷ 27 = 5.93 yd³, then x 1.50 = 8.89 tons. With 5% added, that's 6.22 yd³ and 9.33 tons. A 1-inch bedding layer of stone screenings across the same footprint is 26.7 cubic feet, or 0.99 yd³. Screenings don't have a density on the table above, so confirm their tonnage on the product page.
How much cushion to order
The 5% option is sized for normal compaction and a little rock lost on the ground. Here's how that plays out on typical Texas jobs:
| Situation | What to do |
|---|---|
| Roller-compacted Flex Base on firm clay | 5% box is usually enough |
| Soft or freshly cut subgrade | Round measurements up as well |
| Loose decorative rock | Box optional |
| Long ranch road measured by pacing | Re-measure with a wheel or tape before ordering |
Delivery is arranged at checkout by ZIP code. Give the driver a firm, clear place to dump. After a big rain, a clay pasture won't hold a loaded truck.
Get it on the ground
Take your tons to the product page, choose a date and quantity, and place the order. Delivery is arranged at checkout from the ZIP code you enter: the order is matched to a supplier in the network near that address, and an agent contacts you to confirm the exact delivery address. The Texas locations page is the starting point for anything area-specific, and questions about base depth on your clay go through the contact page.
Common questions
Do I need to order extra rock if I'm laying landscape fabric first?
No. Fabric is thin enough that it doesn't change the volume. Enter the depth of rock you want sitting on top of the fabric.
Should I have it all delivered at once or in stages?
If the base and the top course go down weeks apart, order in stages so the top rock isn't sitting in the way while you compact the base. If you'll place everything in one push, one order keeps things simple.
How do I check the calculator's answer myself?
Multiply length by width in feet, multiply by depth in inches, and divide by 12. Divide that by 27 for yards, then multiply by 1.40, 1.50 or 1.35 depending on the material.
My result falls between two tonnage amounts. Which do I pick?
For base you'll compact, round up. For loose decorative rock on a small bed, rounding down is usually fine. A short load of base is harder to fix later than a small pile left over.
How do I split one project between Flex Base and a top layer?
Run the calculator twice with the same length and width: once with the base depth and the road base setting, and once with the top depth and the right gravel. Order each product separately.
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That tonnage ships free.
Driveway gravel, #57, crusher run: priced by the ton, delivered across Texas.
