Printerpoint provides a visual representation of ink and toner levels currently in your printer.
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The way Printerpoint reports ink levels, and subsequent alerts depends on the manufacturer and the information each printer is willing to divulge. For instance, HP printers will report "Low," "Very Low," and "Empty," whereas a Kip will report only "Low" and "Empty." Here's how it breaks down by manufacturer:
HP: 25% = Low, X% = Very Low, 0% = Empty
Canon: 25% = Low, 0% = Empty
Oce: 25% = low, 0% = Empty
Kip: 25% = Low, 0% (of course) = Empty
Ricoh, Xerox: No support for ink level reporting
In short, an ink cartridge level alert will be generated when its level hits 25% or below, regardless of printer. But, as mentioned earlier, the details below 25% vary by manufacturer.