Bluetooth Is Named After a Viking King
Bluetooth connects your smartphone to wireless earbuds. But did you know that the name comes from a 10th-century king of Denmark and Norway?
Harald Bluetooth - The King with the "Blue Tooth"
The name Bluetooth comes from Danish King Harald I (Harald Bluetooth, c. 910-987). "Bluetooth" was Harald's nickname - some say he had a dead tooth that had turned dark, while others claim he loved blueberries so much that his teeth were stained blue.
King Harald is known for unifying the warring tribes of Denmark and Norway. This achievement of "bringing different things together" is the origin of the Bluetooth technology name.
Bluetooth technology was developed with the goal of connecting devices from different manufacturers using a single wireless standard. The purpose of "unifying different devices" aligned with King Harald's legacy of "unifying different tribes."
The Bluetooth Logo Also Has Viking Origins
The Bluetooth logo (the white symbol inside a blue oval) is a combination of King Harald's initials in runic script.
- "ᚼ" (Hagall) = H (for Harald)
- "ᛒ" (Bjarkan) = B (for Bluetooth)
These two runes overlaid on each other form the familiar Bluetooth logo. Next time you see the Bluetooth icon on your smartphone, remember that a 1,000-year-old Viking script is hidden within it.
Bluetooth Was Originally a "Temporary Name"
In 1996, engineers from Intel, Ericsson, and Nokia were developing a new wireless communication standard. Intel engineer Jim Kardach, who had been reading a historical novel about King Harald, proposed "Bluetooth" as a codename.
A formal name was supposed to be chosen separately, but the candidates "RadioWire" and "PAN (Personal Area Network)" couldn't be used due to trademark issues, and the announcement deadline arrived before a replacement was found. So the temporary name "Bluetooth" became the official name.
The Wi-Fi name also followed the pattern of "a temporary name that stuck," and Bluetooth went through the same process.
Surprising Facts About How Bluetooth Works
- Frequency hopping: Bluetooth communicates by switching between 79 channels in the 2.4 GHz band 1,600 times per second. This prevents interference with Wi-Fi and eavesdropping
- Range: Class 2 (found in smartphones) reaches about 10 m, while Class 1 (industrial) reaches about 100 m. For tips on keeping your smartphone connections secure, see our guide on mobile privacy settings
- Power consumption: Bluetooth Low Energy (BLE) is so power-efficient it can run for years on a single coin cell battery. It's used in Apple's AirTag and other item trackers
- Versions: The latest version is Bluetooth 5.4. Speed has improved roughly 100x since the original version (1.0)
Summary
The name Bluetooth comes from 10th-century Danish King Harald Bluetooth, and the logo combines the runic letters H and B. Including the story of how a "temporary name" became the official one, technology names often hide surprising stories behind them. Bluetooth connects your devices locally, but once they reach the internet, each device is identified by an IP address. You can check your current IP address on IP確認さん.