And the ID badge you use to get in and out of work contains the most bacteria, a study revealed.
The simple security gadget was found to have 243 times more bacteria than a common pet toy.
Researchers from CBT Nuggets - an IT training website based in Oregon - tested everyday working essentials to determine how much bacteria they carried.
They tested five keyboards, trackpads, mouses, electronic badges and phones to determine their average colony-forming units per square inch.
Electronic badges contained 4,620,000 bacteria per square inch while trackpads had just 810 - on average.
They found several types of bacteria had invaded our working and persona lives, including bacilli, gram-positive cocci, gram-positive rods and gram-negative rods.
The former two are responsible for the most sickness bugs - as bacilli are common in food poisoning cases and gram-positive cocci can cause Streptoccal infections.
While gram-negative rods can become resistant to antibiotics but their positive counterpart aren't considered harmful to humans.
Gram-positive cocci were responsible for 42 per cent bacteria found on the five items.
Bacilli made up for around a quarter and gram-negative rods were accountable for 21.5 per cent.
They also found that a trackpad was the better option for anyone worried about potential infections.
It was found to harbour just two forms of bacteria - 67 per cent of gram-positive rods and 33 per cent of gram-positive cocci.
While its alternative - the mouse - contained all four of the different types.