ContainerMath vs SeaRates Load Calculator
A freight marketplace's built-in stuffing tool vs a dedicated planner with saved plans and compliance checks.
The SeaRates Load Calculator is the container and truck stuffing tool inside the SeaRates freight marketplace. It fills standard or custom containers and trucks with boxes, bags, barrels, rolls, pipes and bulk, shows the result in 3D, palletises, lets you set truck axle positions, and exports a step-by-step PDF. Unregistered visitors get a few free calculations a day, registered users a monthly allowance, and a subscription lifts the cap.
Disclosure: this page is published by ContainerMath. We aim to represent SeaRates Load Calculator fairly, cite public sources, and say plainly when it's the better pick. Pricing as of September 2026; verify on searates.com before buying.
Side by side
| Feature | ContainerMath | SeaRates Load Calculator |
|---|---|---|
| Entry price | $39.99/mo Starter, or a $9.99 one-time 7-day pass (one a year); no card to trial | Free allowance; paid plans priced in-account |
| What it is | A dedicated load-planning workspace | A tool inside a freight marketplace |
| AI import of messy manifests | Yes — Starter and up | Manual entry |
| Retail unit → shipper carton (Carton Fit) | Not offered (as of September 2026) | |
| Weight & balance | Payload, CoG envelope, axle & US bridge-formula checks | Truck axle position settings |
| Hazmat segregation (IMDG) | Not marketed | |
| Load-securing estimate (EN 12195-1) | Not marketed | |
| Pipe & cylinder nesting | Physics-accurate hex + telescopic nesting | Pipes as a cargo type |
| Saved plans & history | Every plan, including the free trial | Per calculation; capped allowance |
| Export documents (invoice, packing list) | Pro Plus | Not offered |
| Public REST API | Pro Plus and up | API and white-label on quote |
Where SeaRates Load Calculator wins
Where ContainerMath wins
For a quick, one-off answer to how many boxes fit in a 40ft, the SeaRates calculator is free and needs no account, and if your freight is already booked through SeaRates its premium tier costs nothing for that shipment. ContainerMath is the pick when load planning is a recurring part of the job and the plan, its weight legality and its history have to live somewhere.
What each costs
Free trial (no card) and a free public CBM calculator. Paid plans from $39.99/mo (Starter) to $129/mo (Pro Plus — Carton Fit + container loading, unlimited under fair use, air ULDs, export documents). Flat workspace pricing, 20% off annual billing on every paid plan. Full pricing →
Free: up to 3 calculations a day signed out, up to 20 a month signed in; paid plans lift the cap (prices shown in the SeaRates account, not on a public page); premium is free for the duration of a shipment booked through SeaRates. Source: searates.com (as of September 2026).
Frequently asked questions
Also comparing: vs EasyCargo · vs Cargo-Planner · vs Cube-IQ · vs CubeMaster · vs CargoWiz · vs Goodloading · Full 2026 software guide
Run one real shipment through it
The fastest way to compare is with your own cargo — free trial, no card, a 3D plan in minutes.
ContainerMathThe industry standard for 3D container cargo packing and loading plans. Optimize layouts, maximize volume, and reduce shipping overhead.
Built by Backrock Studios