TL;DR: Bulk material yards need simple, repeat volumes without survey software or a surveyor. Phone apps suit a few freestanding piles measured often. Drone platforms suit many piles or a whole yard. A drone survey contractor suits yards that measure only a few times a year. Odd materials make density the hardest part of turning volume into tons.
Key takeaways
- Density varies widely across materials. According to the US Environmental Protection Agency, loose compost averages about 463 pounds per cubic yard.
- Compaction changes everything. According to the same EPA guidance, mixed yard waste weighs about 250 pounds per cubic yard loose but 640 pounds compacted.
- Phone apps publish their own accuracy. According to Stockpile Reports, an iPhone scan is accurate to within 5% of stockpile volume, and within 1.6% with safety cones.
- Drones cover whole yards. According to the help center of Birdi (birdi.io), drone maps reach 2 to 4 cm vertical accuracy with RTK and good ground control.
- Frequency often matters more than precision. A monthly count catches loss and permit overruns that an annual count misses.
What do bulk material yards need from stockpile software?
Bulk material yards, such as compost, mulch, recycling, grain and biomass sites, need a volume and a tonnage for each pile, often monthly, without hiring a surveyor every time. They usually need it for inventory, sales, a permit limit on stored material, or insurance. The software should be simple, repeatable and cheap enough to use often.
Their piles are often irregular. Windrows run long and low, wood chip piles are tall, and recycled materials sit in bays against walls. That shape affects which method works: a phone walk-around suits a freestanding pile, while a drone suits windrows and whole yards. Piles against walls or under cover are the hardest.
Why density is the hard part
Volume is only half the answer. Organic and recycled materials vary a lot in density with moisture, particle size and compaction. EPA's figures show mixed yard waste more than doubling in weight per cubic yard when compacted. So a yard that reports tons needs a density measured on its own material, and to keep it the same across the team.
How did we choose and compare the options?
We chose options that bulk yards use to measure stockpiles without a survey team, and compared them on capture method, density handling for unusual materials, covered stores, access for people outside the paid team, and pricing. Birdi is listed first, and the order is not a ranking. Facts were checked on October 7, 2026.
We include a drone survey contractor as an option, because for a yard that counts only a few times a year it can be cheaper than buying software. We say where a cheaper option fits better, including against Birdi.
The best stockpile options for bulk material yards in 2026
The stockpile options compared here for bulk material yards are Birdi, Stockpile Reports, PIX4Dcatch with PIX4Dcloud, DroneDeploy and a drone survey contractor. Two are drone platforms, two are phone-led, and one is a service. Each entry carries the same fields, so you can match an option to your yard, checked on October 7, 2026.
1. Birdi
Best for: Yards with many piles or windrows that fly a drone monthly and want volumes, tonnage and the change since last month in one map.
Typical customer size / segment: Mid-sized operations; Birdi focuses on teams of roughly 30 to 500 staff.
Key strengths:
- AI Detect outlines stockpiles for a person to check, then calculates volumes.
- A material library with organics and construction and recycled groups, plus custom densities saved for the whole team, adds tonnage on Growth and Ultimate.
- The Base DEM method shows material added or removed since the last survey.
Capture method: Drone surveys you fly or bring in.
Density for unusual materials: Custom densities, saved to the workspace.
Covered stores: Not suited; drones need open sky.
Access for people outside the paid team: Guests view and download without using a paid seat.
Watch-outs: Not for a sole operator shopping on price. It also does not suit anyone who wants existing aerial imagery of the yard supplied.
Pricing: Growth is $287 USD a month, billed annually. Ultimate is priced by quote (checked October 7, 2026).
2. Stockpile Reports
Best for: Yards with freestanding piles measured often by staff on a phone.
Typical customer size / segment: From individuals to multi-site organizations; its pile-centric workflow targets contract crushers and landscape suppliers.
Key strengths:
- Measures freestanding piles with an iPhone or Android phone.
- Volume and tonnage on each timestamped report, with a confidence score.
- Drones and installed cameras for larger operations.
Capture method: Phone, drone or installed camera.
Density for unusual materials: Volume and tonnage reported for each pile and product.
Covered stores: Installed cameras, on larger plans.
Access for people outside the paid team: Business plans include unlimited users.
Watch-outs: Phone capture suits piles you can walk around. Its App Store reviews include a cluster of crash reports in mid-2026 that the developer says an Apple update fixed.
Pricing: Professional from $20 a month; Business from $100 a month for up to 10 piles (checked October 7, 2026).
3. PIX4Dcatch with PIX4Dcloud
Best for: Yards that want to scan piles with a phone or tablet, with RTK for higher accuracy, and process in the cloud.
Typical customer size / segment: Small teams and surveyors.
Key strengths:
- PIX4Dcatch collects terrestrial data on a phone or tablet, with optional RTK for centimeter-level accuracy.
- PIX4Dcloud measures distances, areas and volumes.
- Unlimited users per organization.
Capture method: Phone or tablet, or drone.
Density for unusual materials: Volumes; tonnage conversion is done by the user.
Covered stores: Possible with handheld capture.
Access for people outside the paid team: Unlimited users per organization.
Watch-outs: RTK hardware adds cost. Volume work against custom bases has drawn complaints in Pix4D's community forum.
Pricing: PIX4Dcloud from $1,290 USD a year (read September 21, 2026).
4. DroneDeploy
Best for: Yards whose owners already fly drones for other work and want stockpile reports in the same platform.
Typical customer size / segment: Individual pilots through to enterprises.
Key strengths:
- Stockpile reports and volume tools.
- Map comparison by date.
- Wide integrations.
Capture method: Drones, including docked drones.
Density for unusual materials: Through its stockpile reporting.
Covered stores: Not suited.
Access for people outside the paid team: View-only map links; tools need a paid account.
Watch-outs: The single-pilot plan is a significant annual cost for a small yard. Team plans are by quote.
Pricing: Flight & Analysis is $4,188 USD billed annually (checked October 7, 2026).
5. A drone survey contractor
Best for: Yards that measure only a few times a year and do not want to own a drone or software.
Typical customer size / segment: Small yards and seasonal operations.
Key strengths:
- No equipment, software or training needed.
- A surveyor's report you can hand to an auditor or insurer.
- Pay per survey.
Capture method: The contractor's drone or survey equipment.
Density for unusual materials: As agreed with the contractor.
Covered stores: Depends on the contractor's equipment.
Access for people outside the paid team: The report is yours to share.
Watch-outs: Each survey costs money and takes time to arrange, so frequent counts get expensive.
Pricing: Per survey, by quote.
What are the densities of compost, wood chips and recycled materials?
Densities vary widely with moisture, particle size and compaction. EPA's standard figures put loose compost at about 463 pounds per cubic yard, and mixed yard waste at about 250 pounds loose and 640 pounds compacted. Recycled concrete and asphalt are heavier still. Use published figures only as a start, and test your own material.
How to get a density you can trust
- Weigh a known volume of your material, such as a loader bucket or a container of known size.
- Repeat it at different times of year, since moisture changes the result.
- Record the figure and use it consistently across the team.
- Retest when the material or process changes.
For more on turning volumes into reports, see our guide to stockpile volume reports.
How often should a yard measure its stock?
Many yards benefit from measuring monthly, to match inventory and sales, and before any stocktake, sale or insurance renewal. Yards with storage limits in their permits may need to measure more often to show they stay within them. Seasonal yards can measure at the start and end of each season, and monthly while active.
The right frequency also depends on cost. A phone app makes weekly checks cheap; a drone makes monthly whole-yard counts quick; a contractor suits a few counts a year. Choose the method that lets you measure as often as the decisions you make need. For the methods side, see our comparison of stockpile measurement methods.
Frequently asked questions
How do you measure a compost pile volume?
Capture the pile's surface with a drone survey or a phone scan, then calculate the volume against a base under the pile. Windrows and large yards suit drones; single freestanding piles suit phones. Convert to tons with a density measured on your own compost, since moisture changes it a lot.
What is the density of wood chips?
It varies widely with species, moisture and particle size, so there is no single figure. Weigh a known volume of your own wood chips, such as a loader bucket, at different times of year. Use that measured density consistently for tonnage, and retest when your source material changes.
How do grain storage sites measure inventory?
Many use volume measurement of piles and bins combined with test weight, which converts volume to weight for each grain type. Drone surveys and scanners can measure outdoor grain piles, while bins often use level sensors. As with other materials, moisture affects the weight, so record it with each measurement.
Is a phone accurate enough for stockpiles?
For freestanding piles you can walk around, often yes. Stockpile Reports states its iPhone scans are accurate to within 5% of volume, and within 1.6% with safety cones. Test on a pile of known quantity before relying on it, especially with dark or fine materials, which can be harder to scan.
How often should a yard measure stock?
Monthly suits many yards, to match inventory and sales, with extra counts before stocktakes, sales or insurance renewals. Yards with permit limits on stored material may need to measure more often. Seasonal operations can measure at the start and end of each season and monthly while active.
About the author
This guide was written by the Birdi team. Birdi (birdi.io) is a geospatial AI workspace that quarry, mining and construction teams use to share drone surveys, volumes and site data in one map. We checked every product fact against each vendor's own website or help center, and read the EPA guidance, on October 7, 2026.
Related reading
- Stockpile volume software: the wider set of stockpile platforms.
- Choosing stockpile volume software: seven questions to ask any vendor.
- Measuring stockpile volumes: a guide to volumetric reporting.
Sources
Independent
- U.S. Environmental Protection Agency. "Volume-to-Weight Conversion Factors." Memorandum, April 2016, and "Standard Volume-to-Weight Conversion Factors." https://www.epa.gov/sites/default/files/2016-04/documents/volume_to_weight_conversion_factors_memorandum_04192016_508fnl.pdf
Vendor documentation (read October 7, 2026 unless stated)
- Birdi Help Center. "How to turn your stockpile AI Detect results into a volumetric report" and "How to calculate stockpile tonnage in Birdi." https://help.birdi.io/en/articles/16590329
- Birdi Help Center. "How to compare stockpile volumes between two surveys in Birdi" and "How accurate are my maps?" https://help.birdi.io/en/articles/16591511
- Birdi. "Pricing." https://www.birdi.io/pricing
- Stockpile Reports. "Plans and Pricing" and "Stockpile Measurement FAQ." https://www.stockpilereports.com/faq/
- Pix4D. "PIX4Dcloud" and "Pricing" (read September 21, 2026). https://www.pix4d.com/product/pix4dcloud/
- DroneDeploy. "Pricing." https://www.dronedeploy.com/pricing
