The price calculator

The calculator exists because a published price is not a cost until someone supplies a volume. Give it one and it works every plan out at the vendor's own rate.

What you give it

Two numbers: how many documents a month, and how many pages each. Between them they determine every unit in the catalog — pages are documents times pages-per-document, documents are documents, and a subscription ignores both.

What it gives back

For each plan, one of four answers:

A cost. The monthly total, plus the effective per-page figure so that plans charging in different units land on a comparable line. Where the volume runs past the plan's allowance, the breakdown shows the base fee, how far over you went, the unit that cap is counted in, and the overage rate applied.

Included. The plan charges for a period and publishes no allowance, so your volume does not change the bill. This is the honest answer, and it is the place most comparison tables quietly substitute a fee divided by an assumed volume.

Over the limit. The plan publishes a hard cap your volume exceeds, with no overage rate — so the plan cannot serve you at all, at any price. The cap is reported in the unit the vendor published it in, whether that is pages or documents, per document or per month.

Not comparable. The plan's unit cannot be derived from documents and pages — per-minute video pricing, or a credit whose definition is the vendor's own. Showing a number here would mean inventing a conversion.

The arithmetic

All money is held as four-decimal strings and every calculation runs on integer ten-thousandths. This is not fussiness: in floating point 0.05 * 3 is 0.15000000000000002, and since the display code reads its precision off the string it is given, a float would not merely round badly — it would render a per-page rate at the wrong number of digits.

A metered plan carries a base price and an overage price as separate rows, and they are selected by their flag rather than by position, so a plan whose overage was entered after its monthly fee still costs as a $15 subscription rather than a $0.05 one.

What it is not

It is not a quote. It uses published list rates, so it knows nothing about your discount, your contract minimum, or what a salesperson will do at the end of a quarter. Treat it as the floor of a conversation rather than its conclusion, and check the figures against the provenance marks on each listing.