Sources
Every figure on this site points at one of the sources below, and the build refuses to publish a fact that does not. Each page lists the specific sources it draws on.
Published sources
| Source | Publisher | Licence |
|---|---|---|
| Wikidata | Wikimedia Foundation | CC0 1.0 |
| The World Factbook | Central Intelligence Agency | Public domain (US Government) |
| OurAirports | OurAirports | Public domain |
| Guide for the Use of the International System of Units (SP 811) | NIST | Public domain (US Government) |
| The International System of Units (SI Brochure) | Bureau International des Poids et Mesures | — |
| Noise-Induced Hearing Loss | National Institute on Deafness and Other Communication Disorders | Public domain (US Government) |
| What Noises Cause Hearing Loss? | Centers for Disease Control and Prevention | Public domain (US Government) |
| Occupational Noise Exposure | Occupational Safety and Health Administration | Public domain (US Government) |
| ENERGY STAR Product Specifications | US Environmental Protection Agency | Public domain (US Government) |
| Residential Energy Consumption Survey | US Energy Information Administration | Public domain (US Government) |
| FoodData Central | US Department of Agriculture | Public domain (US Government) |
| Hypertext Transfer Protocol (HTTP) Status Code Registry | IANA | — |
| RFC 9110: HTTP Semantics | IETF | — |
| Media Types Registry | IANA | — |
| Unicode Common Locale Data Repository | Unicode Consortium | Unicode License |
| Smithsonian National Museum of Natural History | Smithsonian Institution | — |
| The IUCN Red List of Threatened Species | International Union for Conservation of Nature | — |
| National Oceanic and Atmospheric Administration | NOAA | Public domain (US Government) |
| NASA | National Aeronautics and Space Administration | Public domain (US Government) |
| United States Geological Survey | USGS | Public domain (US Government) |
| US Food and Drug Administration | FDA | Public domain (US Government) |
| Food Safety and Inspection Service | US Department of Agriculture | Public domain (US Government) |
| US Environmental Protection Agency | EPA | Public domain (US Government) |
| Evolution of Conversations in the Age of Email Overload | Kooti et al., Proceedings of WWW 2015 | — |
| A new predictive equation for resting energy expenditure in healthy individuals | Mifflin et al., American Journal of Clinical Nutrition 51(2), 1990 | — |
| Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate | Institute of Medicine, National Academies Press, 2004 | — |
| Quantitative Translation of Dog-to-Human Aging by Conserved Rate of DNA Methylation | Wang et al., Cell Systems 11(2), 2020 | — |
| Derivation of New Readability Formulas for Navy Enlisted Personnel | Kincaid et al., US Navy Research Branch Report 8-75, 1975 | — |
| How many words do we read per minute? A review and meta-analysis of reading rate | Brysbaert, Journal of Memory and Language 109:104047, 2019 | — |
| Animal Poison Control Center — toxic and non-toxic lists | ASPCA | — |
| MSD/Merck Veterinary Manual | Merck & Co. | — |
| Web Server Survey | Netcraft | — |
| ICT Facts and Figures / World Telecommunication Indicators | International Telecommunication Union | — |
| Recommended Amount of Sleep for a Healthy Adult: A Joint Consensus Statement | Watson et al., Sleep 38(6) / Journal of Clinical Sleep Medicine, 2015 | — |
| Recommended Amount of Sleep for Pediatric Populations: A Consensus Statement | Paruthi et al., Journal of Clinical Sleep Medicine 12(6), 2016 | — |
| Normal Human Sleep: An Overview | Carskadon & Dement, Principles and Practice of Sleep Medicine, 6th ed., 2017 | — |
| Response Times: Their Role in Inferring Elementary Mental Organization | R. Duncan Luce, Oxford University Press, 1986 | — |
| A comparative study of visual and auditory reaction times on the basis of gender and physical activity levels | Jain et al., International Journal of Applied and Basic Medical Research 5(2), 2015 | — |
| A Policy on Geometric Design of Highways and Streets (the Green Book) | American Association of State Highway and Transportation Officials | — |
| World Health Organization | WHO | — |
| World Bank Open Data | The World Bank | CC BY 4.0 |
| World Population Prospects | United Nations | — |
Our own working
Two citations refer to work done here rather than to an outside publication. They exist so that a computed or compiled figure is never presented as though someone else measured it.
- Official vendor product documentation
- At One Place
- Historical cost of computer memory and storage
- Compiled from contemporaneous retail advertising and manufacturer price lists
- Calculated on this page
- At One Place
- Typical range compiled from manufacturer specifications
- At One Place
“Calculated on this page” marks arithmetic — conversions, ratios, totals — where the inputs carry the real citations. “Typical range compiled from manufacturer specifications” marks figures where no single authority publishes a number and the honest answer is a range across real products.