Convertly

Subscription, freight & energy calculators

Track recurring subscription costs, calculate freight dimensional weight, compare parcel packing, and estimate appliance phantom-load energy.

Subscription Stack & Hidden Inflation Tracker

Normalize monthly and annual plans, compare original prices with today, and see which recurring charge has grown the most.

Your subscriptions

Freight Volumetric Weight & Packing Optimizer

Compare your current box with a proposed smaller package. Billable weight is the greater of actual and dimensional weight.

Current package

Proposed package

Home Appliance Phantom Load Calculator

Estimate the electricity used while devices are idle, asleep, or waiting in standby mode.

Standby devices

How are these costs calculated?

How does the subscription tracker compare plans?

Each annual plan is divided by 12, then added to monthly plans. Stack inflation compares the normalized original annual cost with the current annual cost. The five-year run rate holds current prices constant; it is not a prediction.

What is dimensional weight?

Dimensional weight equals length multiplied by width and height, divided by the carrier divisor. The optimizer compares that result with actual weight for both boxes and uses the larger value as billable weight.

Assumptions and limitations

Does lower billable weight guarantee a lower price?

No. Carrier zones, service level, surcharges, minimums, rounding rules, negotiated rates, and package limits can change the final charge. Use the divisor from your own carrier agreement.

What is phantom load?

Phantom load is electricity consumed while equipment is not doing its primary job. Annual energy equals watts multiplied by standby hours and days, divided by 1,000. Actual draw varies by model, settings, and operating state.