Qi wireless charging
Also known as: Qi2, wireless charging, MagSafe, WPC, inductive charging
Qi (pronounced 'chee') is the dominant wireless charging standard developed by the Wireless Power Consortium.
Devices and chargers that both support Qi work together regardless of brand. Apple, Samsung, Google, and most smartphone manufacturers support Qi, making it effectively the universal wireless charging standard for consumer electronics.
Qi wireless charging, explained at three levels
At home
Qi is the wireless charging system used by most smartphones. You set your phone face-up on a charging pad, and it starts charging without plugging in a cable. The pad and phone don't need to be from the same brand: they just both need Qi support.
At work
Qi charging pads are now standard in many offices, hotels, and airports. As long as an employee's phone supports Qi (most modern smartphones do), they can charge on any compatible pad. This is the result of the Qi standard making different brands interoperable.
At home
Qi uses electromagnetic induction between coils. Charging speed depends on both the charger's output wattage and the phone's receiver capability. Standard Qi: 5-15W. Qi2: 15W with magnetic alignment, and 25W on newer Qi2 chargers and phones. Proprietary fast charging (Apple MagSafe at 15W, Samsung Fast Wireless at 15W) requires matching chargers: a standard Qi charger may only deliver 5-7.5W to these phones.
At work
Qi2 standardizes the magnetic alignment ring (adopted from Apple's MagSafe) for Qi2-certified chargers, ensuring consistent positioning for maximum charging efficiency. This reduces the misalignment problem that caused slow or failed wireless charging. Qi2 certification requires WPC (Wireless Power Consortium) compliance testing.
At home
Qi uses resonant inductive coupling at 100-205 kHz. Power transfer efficiency is 60-80%, with the remainder dissipated as heat, which is why wireless charging is slower and warms the device more than wired charging. The communication protocol between charger and device negotiates the charging power and monitors temperature to prevent overheating.
At work
Wireless charging infrastructure integration (embedding Qi pads in furniture, desks, and vehicles) requires careful RF shielding from nearby metal components that disrupt the electromagnetic field. Foreign object detection (FOD) is a Qi safety feature that detects conductive objects (coins, keys) on the charger pad and halts charging to prevent heating. Qi's Extended Power Profile (EPP) specifies the communication protocol for high-power (>5W) devices.
Real-world examples
At home
Sophie has a Qi charging pad on her nightstand. She sets her iPhone down before sleeping; it charges overnight without her needing to find the cable in the dark. In the morning it's fully charged.
At work
Marcus's co-working space installed Qi charging spots recessed into desk surfaces. Members with Qi-compatible phones charge passively while working, without needing to bring chargers. The facility uses Qi2-certified pads to support faster charging for newer devices.
Common confusions
- Any Qi charger gives the fastest wireless charging speed — Maximum wireless charging speed requires matching charger and device. A 5W generic Qi charger delivers 5W to any phone. A 15W fast charge requires a charger and device both supporting the same fast wireless charging protocol (MagSafe, Samsung Fast Wireless, or Qi2).
- Wireless charging is as fast as wired charging — Wired charging is typically 2-5x faster than wireless at equivalent wattages because wired has higher efficiency. A 65W wired charger charges far faster than a 15W wireless pad, even accounting for the wattage difference.
For analysts
Wireless charging infrastructure in offices and hospitality venues is a real estate and facilities consideration: procurement of Qi2-compatible charging furniture and accessories is a growing category for workplace experience BAs.
History & origin
The Wireless Power Consortium formed in 2008 and published the first Qi specification in 2010. It uses inductive charging: an electromagnetic field transfers energy between two coils, one in the charger and one in the device. Early Qi charged at 5W; later versions reached 15W. Qi2 (2023) added magnetic alignment based on Apple's MagSafe design, and a 25W version of Qi2 followed in 2025.