Shipping Scale for Large Packages: How to Weigh Big Boxes on a Floor Scale
Short answer: a shipping scale for large packages is a low floor platform for boxes too big for a bench or postal scale. Use one long enough for the whole box, with a capacity above your heaviest package. Weigh the box, measure its length, width and height, and enter both in your carrier’s rate tool or shipping software before you buy the label. The carrier’s own scales and dimension readers set the weight you are billed, so your scale is for planning and for catching errors before pickup. The MNM Scales Optima OP-922 is a 660 lb by 0.2 lb, 20 x 43 inch platform scale with a 2.6 inch low profile.
End-of-year sale: $268 on the OP-922 (#43666). Contact us or call (832) 290-3120 with questions.
Platform scale guides from MNM Scales
Bench and postal scales top out at a box about the size of their pan. Once you ship furniture parts, machine parts, rolled goods, long cartons or bundles, the box overhangs the pan and the reading is no longer the whole weight. For everyday parcels and postal software, see our best shipping scale for small business guide; for full pallets, see the floor scale buying guide. This guide covers the space in between: big, heavy boxes on a floor platform.
Why weigh large packages before they ship
- Buy the right label: a label bought on a guessed weight is often adjusted later by the carrier, and the difference shows up on your bill.
- Quote shipping to your customers: a real weight and real dimensions give you a quote close to what the carrier will charge you.
- Choose parcel or freight: carriers set weight and size limits for a single parcel. Knowing the weight tells you early when a shipment belongs on a pallet as freight.
- Catch packing mistakes: a box that weighs far less or more than the same order last week may be missing a part or holding an extra one.
Carriers bill from the weight and dimensions their own equipment records, and large, light boxes are often billed by dimensional weight, which comes from the box size. That is why you measure every large box as well as weigh it. Your carrier’s rate guide explains how it calculates dimensional weight for your service.
What size shipping scale do you need?
A shipping floor scale (some call it a floor shipping scale) sits flat on the floor so you can weigh big cartons, crates and bundles. It is also the answer when you need a scale for packages without pallets: boxes too big for a bench but too small to need a pallet scale.
| Package | Scale | Why |
|---|---|---|
| Envelopes and small parcels | Postal or bench shipping scale (see our guide) | Fine steps, small footprint, postage software |
| Large boxes, long cartons, bundles and crates | Low floor platform such as the 20 x 43 inch OP-922 | Whole box on the deck; capacity for heavy parts |
| Full pallets | 4 x 4 ft pallet floor scale (floor scale guide) | Pallet footprint and forklift loads |
The OP-922 as a large-package scale
The OP-922’s 20 x 43 inch deck takes long cartons that never fit a bench pan, and its 65 mm (2.6 in) height lets you slide or tip a heavy box on without a ramp. It weighs up to 660 lb (300 kg) in steps of 0.2 lb / 0.1 kg (1/3000), with lb and kg on the UNIT key. The LP7515 LCD indicator has a HOLD key that keeps the reading on the display after you lift the box off, and at 18 kg (about 40 lb) the platform moves between the packing table and the dock. For indicator settings, see our LP7515 indicator guide.
| Item | MNM Scales Optima OP-922 (#43666) |
|---|---|
| Capacity | 660 lb (300 kg) |
| Graduation (readability) | 0.2 lb / 0.1 kg (1/3000) |
| Platform | 20 x 43 in nominal (510 x 1120 mm) |
| Construction | Powder-coated mild steel frame with a 430 stainless steel cover |
| Mat | Anti-slip rubber mat, included |
| Platform height | 65 mm (2.6 in) |
| Load cells | 4 aluminum single-point load cells |
| Display | 6-digit backlit LCD on the LP7515 LCD indicator |
| Indicator keys | ON/OFF, ZERO, UNIT and HOLD |
| Hold | Yes: the HOLD key locks the weight of a moving animal |
| Units | lb and kg |
| Power | DC 6 V adapter or batteries |
| Scale weight | 18 kg (about 40 lb) |
| Use | In-house weighing: animals, packages, kegs, sacks and gear for your own records |
| Price | End-of-year sale: $268; contact us or call (832) 290-3120 |
Which boxes fit a 20 x 43 inch deck
| Box footprint (L x W) | Fits flat on the deck? | Tip |
|---|---|---|
| 24 x 18 in | Yes | Center it; room left for a second small box |
| 40 x 18 in | Yes | Long cartons for rails, rods and rolled goods |
| 43 x 20 in | Exactly the deck size | Make sure no edge rests on the floor |
| 36 x 24 in | Stand it on its narrow side, or use a tared cart | A box wider than 20 inches overhangs if laid flat |
| 48 x 40 in (pallet) | Use a pallet floor scale | See the floor scale buying guide |
How to weigh a large package on a floor scale
- Set the platform on a flat, solid floor and keep all four corners clear of walls, pallets and cords.
- Turn the LP7515 indicator on with nothing on the deck and let it zero.
- If you weigh the box on a cart, dolly or tray, put it on first and press ZERO so it reads zero.
- Place the load in the middle of the deck so nothing hangs over an edge or touches the floor.
- Wait for the reading to settle, or press HOLD to lock it, then write it down.
- Clear the deck and check that the display returns to zero before the next load.
Measure length, width and height to the outside of the box, round the way your carrier’s rate guide asks, and enter the weight and the dimensions together. Log both with the order number so you can compare them with the carrier’s invoice.
Tips for a busy shipping area
- Keep the scale where boxes are sealed, so every box is weighed after the last item goes in.
- Keep tape guns, knives and paperwork off the deck; anything resting on it is weighed with the box.
- Check the scale each morning with a box or weight you know, and recalibrate if the reading drifts.
- Tare a hand truck or dolly (not included) so heavy boxes can be rolled on and weighed in one move.
- Keep the indicator cable out of the walkway and away from pallet jack wheels.
Notes from our Cypress, TX shop
- Weigh after the last item goes in: a box weighed before the last part or the packing went in will not match the carrier’s weight.
- Check daily with a known box: keep one sealed box of known weight by the scale; if today’s reading differs from yesterday’s, call us before a week of labels goes out.
- Corners on a long deck: a long carton loads one end more than the other. At calibration our TDA-registered technicians test each corner and the center with their own test weights.
- Bring it in or ship it: drop the scale at our Cypress shop by appointment, use mail-in calibration, or book on-site service when you have several scales.
Our TDA-registered technicians install and calibrate shipping and warehouse scales across the Houston area. Recently they installed a floor scale and a livestock scale kit for a major logistics center near IAH in Houston.
When the weight becomes a charge
Weighing your own boxes to plan labels and freight is an in-house use. If you charge your customers shipping by weight from your own scale, that weight sets a charge. The OP-922 is built for in-house weighing, and it is sold as a vet scale for weighing animals for health and growth tracking. It is not NTEP approved, so it is not a legal-for-trade scale. When the weight sets a price or a charge in Texas, use an NTEP approved scale, and contact us for NTEP options. Our guide to NTEP and legal-for-trade scales explains the classes, and the legal-for-trade scale checker helps you match a scale to a use. Scales used in trade also follow NIST Handbook 44.
Texas note: TDA does not require an NTEP certificate for every device, but the scale must meet NIST Handbook 44 and suit its use; some scales do need one, so we recommend NTEP models and can check yours. See TDA’s scales used in trade guidance (PDF) and our TDA scale certification guide, or call us or TDA to confirm your use.
Ready to order? The MNM Scales Optima OP-922 is a 660 lb by 0.2 lb, 20 x 43 inch platform with a 430 stainless cover on a powder-coated mild steel frame, an anti-slip rubber mat and an LP7515 LCD indicator, End-of-year sale: $268 (see the listing for current stock). Shipping full pallets too? See the floor scale buying guide. Want it calibrated before it ships? Add in-house calibration with a certificate or NIST calibration with a NIST-traceable certificate, or ask us for a calibration quote. Questions? Call (832) 290-3120.
Shop the OP-922 (#43666) Call (832) 290-3120 Request a quote
Calibration, repair and rentals
- Calibrated before it ships: in-house calibration with a certificate or NIST calibration with a NIST-traceable certificate for the OP-922’s capacity; contact us for a quote. See NIST vs in-house certificates and how to calibrate a floor scale.
- On-site service: on-site calibration is $295 plus $2 per mile per visit, plus the calibration fee for each scale. For floor and platform scales, our TDA-registered technicians bring their own test weights.
- Mail-in calibration: ship the scale to our shop with the mail-in calibration service.
- Cypress pickup by appointment: drop off or pick up at our Cypress, TX shop (21249 FM 529 Rd, Cypress, TX 77433).
- Repair: load cell, cable and indicator problems go to our scale repair bench. A reading that drifts or will not return to zero? Start with why a scale will not zero.
- Rentals: we rent all types of scales; ask about a scale rental for a busy season, an event or while yours is in for service.
Frequently asked questions
What scale do I need to weigh large packages?
Use a low floor platform long enough for the whole box, with a capacity above your heaviest package. A 20 x 43 inch platform takes long cartons that overhang a bench scale.
Does the carrier use my scale’s weight?
Carriers bill from the weight and dimensions their own equipment records. Your scale helps you buy the right label, quote customers and catch packing errors before pickup.
What is dimensional weight?
A billing weight calculated from the box size. Large, light boxes are often billed by it, so measure length, width and height as well as weighing every large box.
Can I weigh a pallet on a 20 x 43 inch scale?
A standard pallet is larger than the deck, so it would overhang. Use a pallet floor scale for full pallets and the 20 x 43 inch platform for large boxes.
Do I need an NTEP scale for shipping?
For your own planning, an accurate, calibrated scale does the job. If you charge customers shipping by weight from your scale, use an NTEP approved scale; in Texas, contact us and we can check your use.
How often should a shipping scale be calibrated?
We suggest at least once a year and after the scale is moved, dropped or repaired. Check it daily with a known weight in a busy shipping area.