Hygiene & Bacteria
The Dirtiest Objects in Your Household – A Ranking
The toilet isn't the germiest spot in the house – mop heads, sponges and cutting boards are. A data-based overview of the most heavily bacteria-laden everyday objects, from smartphones to handbags.
The surprise: the toilet actually holds up rather well
A toilet seat is dry and cool – conditions that bacteria, which prefer damp, warm environments, tend to avoid. According to a Statista overview, a toilet seat carries around 33,000 bacteria per ten square centimetres – far less than many objects considered 'clean'.
The frontrunners in the kitchen
- Mop head: around 1 billion bacteria per ten square centimetres – by far the highest value in the overview.
- Kitchen sponge: around 100 million bacteria per ten square centimetres. Germany's Federal Centre for Health Education (BZgA) therefore recommends using cloths and towels instead, washed regularly at high temperature.
- Cutting board: a University of Arizona study found around 200 times more faecal bacteria on cutting boards than on an average toilet seat – especially after cutting raw meat. Plastic boards were found to be more susceptible than wooden ones, since some types of wood have antimicrobial properties.
- Fridge: on average, 11.4 million germs per square centimetre were found, particularly at the back wall, where condensation collects.
Digital everyday companions: smartphone and keyboard
- Smartphone: up to 12 times more bacteria than a toilet – understandable, given a smartphone is picked up around 3,000 times a day on average and held directly against the face during calls.
- Keyboard and mouse: lab tests found up to 400 times more bacteria than on a public toilet – made worse by food crumbs falling between the keys.
Personal items: handbags, make-up, face masks
A study by British hygiene service provider Initial Washroom Hygiene found that one in five handbags carries a bacterial load high enough to pose a health risk – the dirtiest single item inside was often an old hand cream tube.
An experiment by contact lens retailer Lenstore testing 19 everyday items found an average of 1,100 bacteria on make-up brushes – far more than on other cosmetic products tested. Face masks tested came in at an average of 424 bacteria, up to 11 times more than a phone screen (38 bacteria in the same test).
The single highest bacterial load in the entire Lenstore test, however, wasn't found on an object at all, but under people's own fingernails: around 50,000 bacteria on average.
What these numbers mean for your glasses
Direct numerical comparisons between studies using different methodologies should be treated with caution. But one recurring factor across all the research cited here is clear: objects with frequent hand or face contact – smartphones, keyboards, handbags, and yes, glasses too (see How many bacteria live on a pair of glasses?) – are consistently more heavily colonised with bacteria than their 'clean' everyday appearance would suggest.
Frequently asked questions
Is the toilet really cleaner than my phone?+
According to the studies cited here, yes – a toilet seat is usually cleaned more regularly than a smartphone, which is constantly in hand and rarely disinfected.
How often should I clean my smartphone?+
Given the constant hand and face contact, experts recommend cleaning the screen regularly – at least once a week.
Sources
- Statista-Übersicht zu Bakterienzahlen im Haushalt, zitiert in: Naumburger Tageblatt/MZ, 'Handtasche, Handy: Hier lauern mehr Keime als auf der Toilette'
- Utopia.de: 'Diese 7 Alltagsgegenstände sind schmutziger als deine Toilette' (u. a. University of Arizona Studie zu Schneidebrettern)
- WEB.DE: 'Die neun größten Bakterienschleudern im Alltag' (Kühlschrank, Tastatur, Smartphone)
- 20 Minuten: 'Bakterien im Haushalt: Das sind die ekligsten Gegenstände bei dir zu Hause' (Lenstore-Experiment, 19 Alltagsgegenstände)
- Initial Washroom Hygiene Studie zu Handtaschen, zitiert in: Utopia.de
Author: Moritz Weinert, Gründer NURO Labs · Last updated on 3 September 2026