Meet DimShave: Ship Smaller — Beat USPS dimensional weight

Business

DimShave: Ship Smaller

Beat USPS dimensional weight

What DimShave: Ship Smaller does

On July 12, 2026, USPS quietly rewrote the math on every package you ship. The dimensional-weight divisor dropped from 166 to 139, dimensions now round up to the whole inch, and on anything over one cubic foot you are billed for the size of the box, not the weight of what's inside. For eBay, Poshmark, Mercari, and Whatnot sellers, that is roughly a 19% jump in billable weight on bigger boxes — you are paying to ship air.

DimShave fixes it before you pay. Point a LiDAR iPhone at your item and DimShave measures its length, width, and height in seconds. No LiDAR, or testing on a simulator? Type the dimensions or load a sample — you still get a real recommendation. Then an offline engine searches a bundled box catalog and picks the smallest box your item actually fits in, ideally one that stays under the 1,728 cubic-inch line so you are billed on actual weight instead of dimensional weight. It shows you the billable pounds — 'billable 3 lb vs actual 1 lb' — with the full 139-divisor math laid out, before you print a label.

Toggle between USPS, UPS, and FedEx (all three use the 139 divisor for 2026 retail Ground) to see the cheapest option by billable weight, and log every shipment so you can see how many pounds of dimensional weight you have shaved off over time.

Everything runs on your phone. No account, no server, no upload — your measurements and your shipment log never leave the device.

DimShave is an estimating and packing tool, not official postage. Always confirm the final charge with your carrier before you ship.

• AR LiDAR object measurement — L × W × H in seconds • Smallest-compliant-box picker from a bundled catalog, under the 1,728 cu-in threshold • Full 2026 dimensional-weight math with the new 139 divisor and whole-inch rounding • Billable-vs-actual weight, so you see the DIM penalty before you pay • USPS / UPS / FedEx cost comparison by billable weight • Shipment log with a running tally of pounds of DIM avoided • 100% offline and private — nothing is uploaded • Manual entry + sample items when LiDAR isn't available

A look inside

Tap any screenshot to open the full-resolution version.

What's inside

• Scan to size — Measure an item's dimensions in seconds.
• Smallest compliant box — Beat the dimensional-weight threshold.
• Billable weight — See DIM vs actual across carriers before you pay.

Why we built it

After the July 2026 USPS DIM change, resellers overpay on oversized boxes and can't see billable weight before shipping.

What makes it different

ARKit LiDAR measures your item and picks the smallest box under the DIM threshold, showing billable weight with the new 139 divisor.

Who it's for

Operations leaders and small teams who want a tool in their workflow without buying another platform.

In one line: Beat USPS dimensional weight

Try it

See the Beat USPS dimensional weight for the full feature list, the info table, and support links.

Use DimShave: Ship Smaller, found a bug, or have a feature request? Comments are open below — anonymous is fine.