Tools
Our buying guides explain how to choose. These tools answer the questions that call for a calculation or a match: how much you need, and which one fits your machine. They work on our real data and lead to references you can actually order.
Which cartridge or toner for my printer
Search for your model or a reference: we show the toners, ink cartridges, bottles, drums and ribbons linked to that machine, with today's price.
HP, Canon, Epson and Lexmark
Which printer to choose
Five questions about how you print, and we show the printers in stock that fit — along with what each technology costs to run. The cheapest to buy is often the dearest per page.
Laser, inkjet and ink tank
What UPS rating you need
Add up what you want to protect: we apply the safety margin, convert to VA and point to the rating to aim for. A “1,500 VA” UPS does not deliver 1,500 W.
Watts → VA, margin included
How many cameras on which PoE switch
Count your cameras and access points: we work out the power to reserve, the switch's PoE budget and the minimum standard. Watts decide, not ports.
PoE, PoE+ and PoE++
What TV size for what viewing distance
Measure the distance to the sofa, get the screen size. With the two benchmarks that coexist — living-room comfort and cinema or football immersion.
From 1.5 m to 7 m viewing distance