About Shafqat
I build free, formula-verified calculators for homeowners and contractors. Every calculator on this site is cross-checked against primary sources — USGS for aggregate density, NRMCA for ready-mix and aggregate standards, ASTM C29 for unit weight, and CPSC for playground surfacing requirements — before it goes live. Each source is linked directly on the calculator page so you can verify the numbers yourself.
The problem I kept running into with existing online calculators: they gave a result without explaining the formula, hid their methodology, required a signup, or buried the answer under ads. None of them showed their work or linked to a source you could actually check.
Pea Gravel Calculator exists to fix that for one specific topic. Every calculator here is completely free, requires no registration, and shows its full working — the formula, where it comes from, a worked example with real non-round numbers, and a reference table so you understand what your result means in context.
How Formulas Are Verified
Before any calculator is published, the core formula is verified against at least two independent primary sources and tested against three separate online calculators. For the pea gravel weight calculation, for example: the 100 lb/ft³ density figure is confirmed against USGS Mineral Commodity Summaries aggregate data and NRMCA published weight ranges, then the output is compared against calculator.net, inchcalculator.com, and concalculator.com at five different input combinations. Any discrepancy above 2% triggers a formula review before publication.
Depth recommendations follow the same process. The 9–12 inch playground depth requirement comes from ASTM F1292 — not a general landscaping blog. Drainage aggregate specifications reference ASTM C33. When a recommendation is based on general industry practice rather than a formal standard, the article says so clearly.
Editorial Standards
- Answer first. Every page answers the user's question in the first sentence — no preamble.
- Show the formula. Every calculator displays the formula in plain text with a citation for where it comes from.
- Real worked examples. Examples use specific non-round numbers — a 14 ft 6 in × 10 ft 8 in patio at 2.5 inches depth, not a round "10×10 at 3 inches."
- What people get wrong. Every calculator page includes a section covering the most common mistakes for that specific calculation — the most useful section on most pages.
- Primary source links. Every factual claim that can be verified links to the primary source.
- Quarterly review. Every page carries a "last reviewed" date that moves forward when sources update or standards change.
- Cross-checked output. Every calculator is tested against three independent calculators before publication.
What This Site Covers
Seven specialised pea gravel calculators — coverage, weight in tons, cost, bag count, cubic yards, driveway, and patio — plus eight in-depth guides covering what pea gravel is, how to size it, how to install it, landscaping applications, 2026 pricing, material comparisons, color and type identification, and seasonal maintenance.
The content cluster is built around one user intent: a homeowner or contractor planning a pea gravel project who needs to know how much material to order, what it will cost, and how to install it correctly.
Contact
For formula corrections, calculation questions, or feedback, use the contact form. Calculation errors are fixed the same day. All other messages are read personally and responded to within 2 business days.