Qi & Qi2
Wireless Power · 7 specs
Direct Answer
Qi (pronounced 'chee') is the global open standard for inductive wireless power transfer developed by the Wireless Power Consortium (WPC). Operating at 110–205 kHz, it encompasses Baseline Power Profile (BPP, 5W), Extended Power Profile (EPP, 15W), and Qi2 Magnetic Power Profile (MPP, 15W) with ring-magnet alignment.
Source: Wireless Power Consortium (WPC) Qi Specification v1.0–v2.0 · Last reviewed Aug 28, 2026
Specs
| Governing Body | Wireless Power Consortium (WPC) |
| Specification Versions | Qi v1.0 (2010), Qi v1.2/v1.3 (EPP), Qi v2.0 (Qi2 MPP, 2023) |
| Operating Frequency Range | 110 kHz to 205 kHz (Inductive magnetic coupling) |
| Power Profiles | BPP (Baseline: 5W), EPP (Extended: 15W), MPP (Magnetic: 15W), Ki Cordless (up to 2.2 kW for kitchen appliances) |
| Power Transmission Physics | Near-field electromagnetic induction via planar copper wire coils |
| Communications Channel | In-band digital backscatter modulation (2 kbps ASK packets modulated onto power carrier) |
| Safety Protections | Foreign Object Detection (FOD), thermal throttling, over-voltage/current clamping |
Inductive Coupling and In-Band Communication
Qi transfers power between a primary transmitter coil and a secondary receiver coil via resonant magnetic induction. The receiver communicates control packets (requesting voltage/current adjustments) back to the base station by modulating its load impedance (in-band digital backscatter at 2 kbps), eliminating the need for an external Bluetooth or Wi-Fi radio connection.
Qi2 and Magnetic Power Profile (MPP)
Announced in 2023, the Qi v2.0 standard adopted Apple's MagSafe magnetic ring array as the Magnetic Power Profile (MPP). By locking transmitter and receiver coils into close angular alignment using a circular ring of permanent magnets, full MPP devices reduce inductive coil misalignment losses, improving electrical energy efficiency and reducing battery-degrading heat, with up to 15W charging. Not every 'Qi2 Ready' device includes the magnet ring, though -- some certified phones (e.g. early Samsung Galaxy S25 models) need an added magnetic case to get full MPP alignment and speed, so 15W isn't guaranteed across every certified device out of the box.