For ammunition it reads the round count and works out the cost per round: {costperround price="18.99"}Federal American Eagle 9mm 115gr FMJ 50rd{/costperround} shows "$0.38 per round".

The package contains:
- Content - Firearm Specs plugin: {firearmspecs} and {costperround} tags in articles, category descriptions and Custom modules. Table, description list or one-line layout. You choose the specs to show: type, brand, model, caliber, caliber type, magazine capacity, barrel length, rounds per box and cost per round.
- Cost per Round Calculator site module: the price and round count of a box, or the price and the ammo title ("Federal 9mm 115gr FMJ 50 Rounds"). It works without JavaScript; with JavaScript the result updates while you type.
- GunsNPrices Parser Library: the title parser. Other extensions can use it through the GunsNPrices namespace.

Settings: barrel length in inches, centimeters or millimeters; number format (1,234.56, 1.234,56, 1 234,56 or the separators of the site language); currency symbol and position; format and decimal places of the cost per round. All HTML comes from layout files that templates can override.

Runs on your server. The parser and its data are part of the package. The extensions make no requests to other sites, set no cookies and have no tracking. Links from caliber names to their price comparison pages on GunsNPrices.com are an option that is off by default.

The parser knows 293 calibers with their retailer spellings ("9MM LUGER", "5.56 NATO", "12GA", "300 BLK") and the models of 50 brands. It is the parser behind GunsNPrices, a price comparison site for US gun and ammo stores. Measured on 63,755 store listings, it finds the caliber in 81% of firearm titles and 91% of ammunition titles and is right 95-98% of the time when it finds one. Titles in English from US retailers work best.

Joomla 5 and 6, PHP 8.1 or later. GPL v2 or later; the bundled parser is MIT-licensed and its data is CC BY 4.0.