Seller disclosure: XES Netting sells bale net wrap. This guide is product-neutral: it does not rank a bale size, baler brand, or binding product. The exact machine manuals, measured bale weights, equipment ratings, written customer specifications, and applicable law control.
Quick answer: In round bale notation, WIDTH × DIAMETER means the cylinder's axis length first and circular diameter second. A 5×6 has 141.37 ft³ of ideal cylinder volume, 44% more than a 5×5's 98.17 ft³. That is a volume comparison, not a weight estimate. There is no universal best size: choose only after the exact baler, tractor, loader, downstream equipment, feedout, customer, and transport checks all pass.
The useful question is not simply “4x5 vs 5x5 vs 5x6?” It is: which bale can this complete operation make, handle, store, transport, and use without exceeding its lowest equipment rating or a written specification? The geometry is the easy part. The decision depends on measured bales and the exact machines and route involved.
Round bale notation and volume: WIDTH × DIAMETER
A 4×5 round bale is nominally 4 feet wide along its cylinder axis and 5 feet in circular diameter. The same order applies to 5×5 and 5×6. UF/IFAS uses this width-by-diameter convention and explains that dimensions determine volume, while volume together with density determines weight. UF/IFAS, “Implications of Round Bale Dimensions on Hay Use” (published 2019; modified 2024).
For a nominal bale treated as an ideal cylinder:
Volume = π × (diameter ÷ 2)² × width
| Nominal size (width × diameter) |
Cylinder calculation | Ideal volume | Relative to 5×5 |
|---|---|---|---|
| 4×5 | π × 2.5² × 4 | 78.54 ft³ | 80% |
| 5×5 | π × 2.5² × 5 | 98.17 ft³ | 100% |
| 5×6 | π × 3² × 5 | 141.37 ft³ | 144% |
At the same 5-foot width, a 6-foot-diameter cylinder has exactly 1.44 times the volume of a 5-foot-diameter cylinder: about 44% more. UF/IFAS reports the same 80% / 100% / 144% relative-volume relationship for 4×5, 5×5, and 5×6 bales.
Volume is not weight. Actual bale weight depends on measured diameter, density, crop, moisture, chamber settings, windrow and operating conditions, and other factors. A model or nominal size cannot supply the missing density and moisture measurements. Weigh representative bales with suitable rated equipment; do not infer a handling load from this table.
Nominal dimensions are also not a promise that every finished bale is a perfect cylinder or reaches the maximum diameter. Record the actual diameter and scale weight of representative bales from the crop and settings being evaluated.
4x5 vs 5x5 vs 5x6: a calculator-quality comparison
| Check | 4×5 | 5×5 | 5×6 |
|---|---|---|---|
| Nominal width (axis length) | 4 ft | 5 ft | 5 ft |
| Nominal diameter | 5 ft | 5 ft | 6 ft |
| Ideal cylinder volume | 78.54 ft³ | 98.17 ft³ | 141.37 ft³ |
| What geometry establishes | Volume only | Volume only | Volume only |
| What must be measured or verified | Actual diameter, weight, dry matter, loader load, clearances, customer tolerance, transport envelope, and binding-system fit | ||
| Common fit gate | Exact 4×5-capable baler and every downstream opening | Exact 5×5-capable baler and every downstream opening | Exact 5×6-capable baler plus 6-ft diameter clearance everywhere |
| Transport planning number | The measured transverse load dimension after orientation—not a size nickname such as “two side by side” | ||
Official model examples show capability, not bale weight
Current official product pages provide useful examples of exact model capability: the John Deere 451M is identified as a 4×5 model, the John Deere 551M as a 5×5 model, and the John Deere 561M as a 5×6 model. These labels establish capability for those named models only. They do not establish bale mass, tractor suitability, loader capacity, density, actual finished diameter, or net-roll compatibility.
Round bale size decision tree: stop at the first failed gate
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Can the exact baler make it? Confirm the model, PIN or serial number, installed options, chamber range, binding system, and current operator manual. A family name or similar-looking model is not enough. If the written specification does not support the target size, stop.
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Can the tractor meet every baler requirement? Check the exact PTO, hydraulic flow and pressure, remotes, drawbar, tractor mass, ballast, tire, brake, and slope requirements in both manuals. Do not substitute horsepower alone for the complete requirement list.
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Can the complete handling system lift a measured bale? Use representative scale weights, then check the tractor or telehandler, loader, quick-attach, purpose-built spear/grapple/fork, tires, wheels, front and rear axles, ballast, and brakes. Use the rating at the actual load center and configuration—not a headline lift figure measured at a different point. The lowest equipment rating governs.
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Will it fit every next machine and opening? Measure the wrapper, processor, tub grinder, TMR mixer, feeder, storage door, alley, stack plan, trailer, and unloading site. Include attachment clearance and the space required to approach, turn, and set down the bale safely.
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Does it match feedout? Estimate usable dry matter per measured bale, the animal group's daily requirement, storage loss, and refusal or feedout loss. A smaller bale may better match a small group's feedout interval, but that is an operation-specific result—not a universal rule. Use a forage test and review the ration with a qualified nutritionist or veterinarian.
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Does it match the field and labor plan? Compare actual cycle time, stops, handling moves, field size, terrain, labor, and weather window. A larger-volume bale can reduce bale count at equal density, but it can also create equipment, access, and slower-feedout costs.
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Does it meet the customer's written specification? For hay sold or custom-baled, get width, diameter and tolerance, crop and moisture condition, binding type, delivery orientation, unloading equipment, and any scale or forage-test requirements in writing. Do not assume a buyer or carrier prefers one size.
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Is the measured load legal on the exact route? Check vehicle and trailer ratings, actual axle distribution, brakes, securement, state agricultural rules, permits, height, length, width, route, bridge and road restrictions, and escort requirements. If any gate fails, change the bale size, equipment, load arrangement, or route before operating.
Penn State's large-bale guidance specifically says the tractor and attachment must safely handle the bale's size and weight and calls for bale-specific attachments, ROPS, low carrying height, slow travel, tire-capacity checks, and counterweight as needed. It is general guidance; the exact equipment manuals and ratings remain controlling. Penn State Extension, “Safely Moving and Storing Large Hay Bales”.
Handling safety: the bale must stay controlled
Large-bale incidents include tractor rollover, a bale rolling back onto the operator, people crushed near unsecured bales, attachment failure, and loss of steering or braking. NIOSH's large-bale bulletin calls for suitable maintained equipment, secure load control, proper counterweight, ROPS and seat belt use, a low attachment, and a planned firm route clear of holes, ditches, and ruts. NIOSH/CDC, “Preventing Deaths While Moving Large Hay Bales with Tractors” (2001).
- Use ROPS with the seat belt fastened; ROPS without the belt does not keep the operator in the protected zone.
- Use manufacturer-specified ballast and stay within the ratings of the tractor, loader, attachment, quick-attach, tires, wheels, axles, and brakes.
- Use a purpose-built bale spear, grapple, or fork that secures the bale for the planned movement. Do not use a general bucket as a substitute.
- Carry the bale low and travel slowly. Plan for slopes, holes, ruts, mud, side drop-offs, overhead lines, limited visibility, and stopping distance before moving.
- Keep everyone outside the roll, fall, and crush zones. Never stand under a raised bale or work beneath raised loader components.
- Do not cut or remove net, twine, or film while a bale is raised on forks or a loader.
If binding must be removed
Use a conservative stop-work sequence: place the bale fully on firm ground in a stable position; lower the attachment; set the parking brake; shut the machine down; remove the key; wait for motion to stop; and work from outside the bale's roll, fall, and crush path. Never depend on hydraulics or the attachment to hold a bale over a person. This sequence does not replace the exact machine manual or a site-specific safety procedure.
Remove all net, twine, film, and loose binding fragments before the forage enters a feeder, processor, mixer, or animal-access area. Do not treat binding as edible or as cargo securement.
Transport: orientation changes the measured width
The federal baseline is specific, not universal. For applicable commercial motor vehicles on the National Network, federal rules generally use a 102-inch vehicle-width baseline. FHWA explains that cargo extending beyond 102 inches on the Network and reasonable-access routes requires an overwidth permit. State agricultural exemptions, special permits, local roads, and vehicle classifications vary. FHWA, Vehicle Size and Weight Q&A; 23 CFR § 658.15.
Draw the load before using “side by side”
Width is the bale's axis length; diameter is its circular dimension. The dimension across the road therefore depends on orientation:
road edge ← [ 60 in WIDTH ][ 60 in WIDTH ] → road edge
axes run across the road
total measured transverse envelope = 120 in
Two 5-foot-wide bales placed end-to-end across the road total 120 inches before bulge, lean, restraints, or vehicle components are considered. That exceeds the standard 102-inch baseline absent an applicable state exemption or permit. If the bale axes run with the road instead, the circular diameter becomes the transverse dimension. Never approve a load from “4x5,” “5x6,” or “two side by side” alone—measure the complete transverse envelope in its actual orientation.
Before travel, verify actual loaded weight and axle distribution against GVWR, every GAWR, tire and wheel ratings, hitch and coupler ratings, brakes, and the tow vehicle's limits. Check height, length, width, route, bridge and road restrictions, permits, lighting, marking, and escort requirements with the responsible state and local authorities.
For covered commercial motor vehicles, 49 CFR Part 393, Subpart I requires cargo control that prevents falling or shifting that harms stability or maneuverability and uses performance and working-load-limit criteria. It does not create one universal strap count for every bale load. Cargo arrangement, rolling tendency, blocking, anchor points, restraint method, and device working load limits all matter. Net wrap contains the bale; it is not transport securement.
Storage, feeding, and economics: compare usable dry matter
Storage is a package-and-site decision
Do not claim that geometry alone reduces spoilage per ton. Storage outcome depends on crop, density, initial moisture, binding, base, drainage, cover, row and stack arrangement, climate, and storage duration. Net wrap can shed more rain than twine in tested conditions, but it is an open mesh—not a waterproof cover.
A USDA Agricultural Research Service study abstract reported average dry-matter losses of 19.5% for sisal twine, 11.3% for plastic twine, and 7.3% for net wrap in its specific alfalfa and grass/alfalfa trials stored for 5 or 12 months. The researchers also emphasized the importance of well-drained storage for bale bottoms. Those treatment averages are evidence for those trials, not guaranteed loss rates for another forage, density, wrap, base, climate, or storage period. USDA ARS publication record (accepted 2002).
For each candidate size, document indoor or outdoor storage, base and drainage, cover, row spacing and orientation, stack method, door and roof clearances, retrieval route, fire-department access, and the number of bales that can be stored without unsafe stacking. If heated hay is monitored, use a package- and crop-specific Extension or fire-service protocol rather than transferring a threshold from a different bale package.
Feed by tested dry matter—not bale count
Compare the dry matter delivered and consumed, not the number of bales set out. Pair representative scale weights with dry-matter measurements taken at the same point in time. If the starting measurement is at storage entry, include measured loss from storage entry through feedout. If the starting measurement is current or as-fed, past storage loss is already reflected in that bale and must not be subtracted again. University of Minnesota Extension advises testing forage and matching hay quality and amount to changing cattle nutrient requirements. University of Minnesota Extension, “Efficiently Feeding Hay to Cattle”.
For TMR use, moisture changes alter the actual dry matter entering the mixer, and long forage can create mixing and sorting problems. Penn State recommends routine dry-matter checks and following the mixer manufacturer's instructions. Penn State Extension, “TMR Management—Ensuring Formulated Rations Make it to the Bunk”. Review the ration and meaningful changes with a qualified nutritionist or veterinarian.
A transparent user-input worksheet
Run this worksheet separately for 4×5, 5×5, and 5×6. Use operation records—never a stale national average. For dry-matter accounting, choose Method A or Method B and stay on that time basis; do not combine their loss rows.
| Input or result | Your number | Calculation or evidence |
|---|---|---|
| Method A — representative storage-entry weight | _____ lb | Average from a suitable scale when bales enter storage; record crop, actual diameter, settings, and sampling date |
| Method A — storage-entry DM fraction | _____ | DM measured at the same time as the storage-entry weight; forage-test DM% ÷ 100 |
| Method A — storage-entry DM | _____ lb/bale | Storage-entry weight × storage-entry DM fraction |
| Method A — measured cumulative loss fraction | _____ | Loss from storage entry through feedout, including spoiled material and refusal; use only with Method A |
| Method A — usable DM per bale | _____ lb | Storage-entry DM × (1 − cumulative loss fraction) |
| Method B — representative current/as-fed weight | _____ lb | Average immediately before feeding; record crop, actual diameter, and sampling date |
| Method B — current/as-fed DM fraction | _____ | DM measured at the same time as the current/as-fed weight; forage-test DM% ÷ 100 |
| Method B — current DM before future feedout loss | _____ lb/bale | Current/as-fed weight × current/as-fed DM fraction; past storage loss is already embodied here |
| Method B — future feedout/refusal loss fraction | _____ | Loss from the current measurement point through consumption; do not add historical storage loss |
| Method B — usable DM per bale | _____ lb | Current DM × (1 − future feedout/refusal loss fraction) |
| Annual usable-DM requirement | _____ lb | Nutrition plan by animal group and feeding period |
| Bales required | _____ bales | Annual usable-DM requirement ÷ usable DM per bale from the one method selected above |
| Field and handling labor | _____ hours | Measured cycle time × projected bale count, plus storage and feeding moves |
| One-time capital and cash required | $_____ | Purchase and site-change cash for the baler, tractor, loader, attachment, processor, storage, door, or access; keep separate from annual expense |
| Recurring incremental annual operating cost | $_____ | Actual incremental labor, fuel, repairs, binding, storage operation, feedout, transport, securement, permits, and escorts |
Keep purchase price and loan principal out of recurring annual operating expense. If an annual economic comparison of capital assets is needed, use a consistent capital-recovery method that states service life, residual value, and cost of capital; debt service is a financing cash flow, not the economic return on the asset. A larger bale can reduce bale count when density and total dry matter are held constant, but it can also require more capital, heavier equipment or permits, and slower feedout for a small group. The worksheet reveals the tradeoff; geometry alone cannot guarantee efficiency or profit.
Bale size does not establish net-wrap compatibility
A nominal 4-foot or 5-foot bale width does not prove that a particular net roll fits the baler. Verify the exact model and serial number, installed binding type, approved net width, core specification, holder capacity, maximum package outside diameter, axial package length, spacers, brake or tension system, feed path, and any approved material requirements in the current operator manual.
Use the wrap application setting and loading route from that exact manual. Do not derive a setting from nominal bale size, a different baler, or a strength claim. Vermeer's official manual portal, for example, requests both the machine model and VIN or serial number—an appropriate model-specific pattern for any brand. Vermeer product manuals.
Frequently asked questions
What do 4x5, 5x5, and 5x6 mean for round bales?
The notation is WIDTH × DIAMETER. A 4x5 bale is nominally 4 feet wide along its cylinder axis and 5 feet in circular diameter. A 5x6 is 5 feet wide and 6 feet in diameter.
How much more volume does a 5x6 have than a 5x5?
At the same 5-foot width, the ideal cylinder volumes are 141.37 cubic feet for a 5x6 and 98.17 cubic feet for a 5x5. The 5x6 therefore has about 44 percent more volume.
Does a 5x6 bale weigh 44 percent more than a 5x5?
Not necessarily. The 44 percent figure compares ideal volume at the same width; actual weight also depends on measured diameter, density, moisture, crop, settings, and field conditions. Weigh representative bales.
Which round bale size is best?
There is no universal best size. Choose the size that passes the exact baler, tractor, loader, attachment, tire, axle, brake, downstream-equipment, storage, feedout, customer-specification, and transport checks.
Can two 5-foot-wide bales fit within the standard federal truck width?
Two 5-foot widths total 120 inches when placed end-to-end across the road, which exceeds the 102-inch federal baseline for applicable commercial motor vehicles on the National Network. Exemptions, permits, routes, and state rules vary.
Does bale width tell me which net wrap roll fits?
No. Verify the exact baler model and serial number, binding type, approved net width, core, holder capacity, package outside diameter and axial length, spacers, brake or tension system, feed path, and settings in the current operator manual.
Source and scope notes
- Geometry: UF/IFAS AN326 supplies the width-by-diameter convention and equal-density relative-volume comparison. The three cubic-foot values above are transparent cylinder calculations.
- OEM capability: John Deere's current 451M, 551M, and 561M pages are examples for those exact models only.
- Handling: Penn State and NIOSH provide general large-bale safety controls. The exact machine and attachment manuals supersede this guide.
- Transport: FHWA and current federal regulations are the federal baseline for applicable vehicles and roads. State and local authorities control exemptions, permits, and non-Network routes.
- Storage and feeding: The cited USDA ARS results are limited to the reported trials. University of Minnesota and Penn State feeding guidance does not create a universal bale-size recommendation.
The XES Netting team manufactures bale net wrap and writes product-neutral, source-cited guides for forage operators. This article provides general educational information, not engineering, legal, veterinary, nutrition, or site-specific safety advice.
Featured photo: Round hay bales on a field by DimiTalen, released under CC0 1.0 (Public Domain), via Wikimedia Commons.
