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Docs & Help

General Documentation

How ContainerMath works — the calculators, the 3D results, compliance checks, plans and the developer API. Jump to a topic from the nav on the left (or the chips above), or just scroll.

Overview

Getting Started

ContainerMath plans how cargo fits into shipping containers, trucks, rail wagons, and pallets — and how many products fit into a box. It runs an actual 3D packing engine, not a rough estimate, so what you see in the plan is what fits.

The tools

  • Freight — pack a cargo manifest into shipping containers, trailers, flatbeds, or rail wagons. This is the main dashboard at /.
  • Optimizer — takes a manifest you've already built and recommends the cheapest equipment mix instead of you guessing.
  • Carton Fit — a different question: how many of your products fit inside one box, and how many boxes does an order need.
  • Export Docs — not a calculator: turns a packing list into filing-ready export paperwork for your jurisdiction. Pro Plus and Custom.

Typical workflow

  • Pick the equipment or box you're loading into.
  • Build the load — add cargo items one at a time, paste a manifest with Smart Input, or pull in saved presets from your Item Library.
  • Hit Calculate (or ⌘/Ctrl Enter) — the packing engine runs and returns a real plan, not an estimate.
  • Review the results: fill %, 3D view, weight balance, and any compliance findings.
  • Save the plan, export a PDF/spreadsheet, or open it in AR on your phone.

The tools

Freight Calculator

The main dashboard: choose equipment, build a cargo manifest, and calculate a real 3D load plan.

The vessel picker groups every equipment type into five categories — Shipping Containers, Air (ULDs), Road Trailers, Flatbeds and Rail Wagons — across ContainerMath's 50+ supported vessel types. Each entry shows interior dimensions and max payload up front, and you can filter the list to the equipment standard in your market with the region picker.

Everything except the Air (ULDs) section is available on every plan. Air-cargo ULDs (LD-3, LD-7, LD-11, PMC, PAJ) are a Pro Plus / Custom capability: the rows stay visible and selectable on lesser plans, but picking one prompts an upgrade instead of calculating.

Not sure which one to use? Turn on Compare, tick a few candidates, then run a single calculation — you get every candidate packed side by side (fill %, weight, containers needed) so you can pick the winner before committing.

The tools

Results, 3D & Compliance

Every calculation opens the results panel: utilization, an interactive 3D plan, weight balance, and — where it applies — compliance and loading guidance.

  • Overview / Contents / Capacities / Compliance / Insights tabs — utilization stats and headline numbers, a full manifest breakdown, per-SKU capacity estimates, compliance findings, and AI-written notes + step-by-step loading instructions.
  • Multi-container plans page through each container with a windowed strip of buttons (first … current ± 1 … last), so a 2,000-container plan stays navigable.
  • 3D view — orbit, pan and zoom the packed load; a 2D cross-section/projection view sits alongside it for a flat top/side read of the same container.
  • Weight distribution & axle loads — front/rear (and for road rigs, per-axle) balance, checked against legal limits.

Compliant alternative

On a road vessel, if the plan puts an axle over its legal limit, the Compliance tab doesn't stop at telling you. It searches for an arrangement of the same cargo in the same vehicle that's legal on every axle group — usually by loading the dense cargo toward the doors instead of the bulkhead, and pushing the finished stow back against the doors — and shows it next to the broken plan with both worst-axle figures side by side. One click re-plans onto it.

The card always prints both vehicle counts. Some loads are too concentrated to balance on one vehicle, and the only legal answer is to spread them; when that happens it says so in those words — “1 → 2 vehicles, compliance costs 1 extra vehicle” — rather than quietly adding a truck to your plan. Multi-stop loads keep their drop order: the app won't trade your unloading sequence for axle weight. Where re-stowing pushes the load to the doors, it tells you the gap left at the bulkhead needs bracing.

Compliance vs. advisories — read carefully

The Compliance tab deliberately separates two different things. Compliance issues are reserved for findings with an actual regulatory limit behind them — an axle weight over the legal limit, or a US Federal Bridge Formula violation. Everything else — an off-center center of gravity, front/rear imbalance, a reefer temperature mismatch, securing recommendations — is worded as an advisory: the app flags the problem and cites the relevant guidance, but doesn't claim it's illegal to ship. Both sections link to the specific card with the detail.

Loading Chart

A printable, one-sheet-per-container loading chart for the loading bay: top and side diagrams with numbered loading steps, a loading-sequence table, a colour legend, and a weight/balance summary with a sign-off block. Open it from the plan and use your browser's print dialog (or the on-page Print button) to produce paper copies or a PDF.

The Loading Chart — one printable sheet per container.

Exports

A finished plan can be exported as a Detailed PDF report, a Management Summary PDF, pallet stacking sheets, a PNG/JPG snapshot of the 3D view, CSV/Excel data, or a full ZIP bundle. PDF reports, CSV/Excel data and the ZIP bundle are downloadable on Pro Plus and above — the free trial and Starter review results on screen and can export image snapshots (watermarked on the free trial, clean on Starter and up).

Calc ID

Every calculation shows a short Calc ID at the bottom of the results panel, with a one-click copy button. If something looks wrong with a plan, quote this ID to support — it's a direct reference they (or an admin) can look up.

The results panel with the interactive 3D view.

The tools

Optimizer

Give the Optimizer a manifest and it ranks every candidate — the cheapest configuration wins, with the full comparison and savings shown underneath.

The Optimizer runs on the manifest you've already built in Freight or Carton Fit — there's nothing new to enter. It exists in two flavors that share one page: /optimizer ranks freight equipment (e.g. 1× 40ft HC vs. 2× 20ft), and /carton/optimizer ranks carton/box sizes for a product manifest. A one-click switcher moves between the two.

  • Optimize for lowest cost or best volume fit.
  • Freight runs can take an optional From/To lane and currency, with region-filtered candidates and an estimated freight cost by distance.
  • Enter your own known rates per vessel/box to override the built-in cost estimate — they're saved to your account and reused next time.
  • Results show a recommended pick, the full ranked comparison table, and any vessels/boxes rejected as unsuitable (with why).

The Optimizer is plan-gated: freight needs the equipment-optimizer capability, carton needs the carton-optimizer capability. On metered plans (free trial, Starter) runs are counted per month; paid plans that include it run unlimited optimizations.

The Optimizer — ranked equipment options with cost and savings.

The tools

Carton Fit

A different question from Freight: not 'what fits in a container', but 'how many of my product fit in this box, and how many boxes does an order need'.

Pick a box — from your saved Box Library or an ad-hoc size entered on the spot — add your products the same way you would in Freight, and hit Calculate. The result leads with units per box and boxes needed instead of freight metrics, and groups the actual packed boxes by configuration (so a mixed order shows each distinct box make-up honestly rather than one misleading average). Tap a box-plan row to jump the 3D view to that exact box.

Carton Fit always packs in flat mode (no pipe-nesting heuristics — those are freight-only). Not sure which box to use? The Recommend one shortcut sends your manifest straight to the Carton Optimizer.

Carton Fit keeps its own manifest, history and plan completely separate from the Freight dashboard — switching tools never mixes up or clears the other tool's in-progress work.

Carton Fit — units per box, boxes needed, and the box plan.

The tools

Export Documents

Turn a packing list into filing-ready export paperwork for your jurisdiction — Commercial Invoice, Packing List, Proforma Invoice and the combined Invoice-cum-Packing-List — as branded, print-ready PDFs.

The Export Docs workspace at /export-docs builds one shipment across six tabs — Import, Exporter, Buyer & Consignee, Shipment, Items, and Branding & Bank. Every document carries your letterhead and logo, the party and shipment details, the line-item table with totals and amount-in-words, the GST/LUT declaration and a signatory block. Generate each document individually, or download all four together as a ZIP.

  • Import — paste a packing list or load plan (or upload a .csv/.xlsx file), then choose Smart import (AI, for unstructured text — it streams its progress live and draws on the same token wallet as Stowy) or Parse as table (deterministic, for comma/tab-separated rows).
  • Jurisdiction & compliance checklist — pick the shipment's jurisdiction (India, the EU, US, UK, UAE, Singapore, Australia, Canada or a generic international format) and a live panel tracks the mandatory fields that jurisdiction's export invoice needs — identifiers like IEC & GSTIN or EORI & VAT, invoice number and date, Incoterm, ports, HS-code depth — and jumps you straight to whatever needs attention. Documents still generate while items are outstanding — the checklist just tells you what's missing.
  • Company profile — save your exporter, bank and branding details once at /export-docs/company, and every new shipment starts prefilled from them.

Your in-progress shipment autosaves as a draft in the browser as you type, so a reload never loses work. Saving shipments to your account and AI Smart import need a Pro Plus or Custom plan — on other plans you can still build a shipment by hand, run the compliance check and download every document.

Export Documents — the shipment editor beside the live compliance checklist and one-click PDF generation.

Account

Plans & Billing

ContainerMath is metered by plan — from a free trial up to an unlimited Pro Plus. Every plan carries both calculators; what changes is how much you can run and which deliverables you can take away.

PlanRoughly unlocks
Free trialA handful of free calculations to run a real job, watermarked image exports.
StarterPaid entry tier — 50 calculations a month across freight or carton loads, plus manifest import (AI paste and CSV/XLSX). Can't download PDF reports or CSV data, save plans, or manage custom vessels.
Pro PlusUnlimited calculations across all 50+ vessel types, saved plan history and PDF/CSV downloads, custom vessels and units, air-cargo ULDs, Utilization Insights, the lane calendar, the Export Documents workspace, the REST API and the embeddable widget — the top self-serve plan.
Custom / EnterpriseSales-led — everything in Pro Plus with no fair-use ceiling, unlimited API quota, white-labelled exports (the “Powered by ContainerMath” footer removed) and terms tailored to your volume.

Upgrade any time from Upgrade plan in the account menu — it offers one-click checkout for the plan that unblocks whatever you hit, without losing what you already pay for. Billing itself is managed through your payment provider's own portal. See /pricing for the full feature comparison across every plan.

Account

Developer API

REST API with key auth
Integrate ContainerMath's load planning into your ERP, TMS or CRM.

Create and revoke secret API keys (cm_live_…), read the full endpoint/field reference, and see your monthly request quota — all on the Developers · API page, reachable from the account menu. The API is available on the Pro Plus and Custom plans, with a monthly request allowance on Pro Plus and no cap on Custom.

Embeddable widget

The same page mints publishable keys (cm_pk_…) for the embeddable calculator widget. Unlike the secret keys these are safe to ship in browser JavaScript, because each one only answers requests from the domains you bind to it — a key with no domains bound serves nothing. Drop the script tag on your site with the key in data-key and visitors get a calculator without leaving your page. Also Pro Plus and Custom, and re-checked against the key owner's current plan on every request, so a key stops working if the account drops below it.

Read the API reference

Help

FAQ & Support

Contact support
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Getting Started

Start here — what ContainerMath does and the tools you'll use.

ContainerMathContainerMath

The industry standard for 3D container cargo packing and loading plans. Optimize layouts, maximize volume, and reduce shipping overhead.

Built by Backrock Studios
3D Container Loading CalculatorCargo Stacking SoftwareSea Freight Packing OptimizerFreight Cube UtilizationContainer Load PlannerLogistics Stowing AlgorithmNesting & Bundling Calculator2D/3D Container Stowage PlanTruck & Trailer Cargo PackerPallet Load OptimizationLogistics Dispatch SoftwareBackrock Studios

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