Q40

Q40 may refer to:
 * Q40 (motherboard), compatible with the Sinclair QL
 * Q40 (New York City bus)
 * Al-Shamikh, a corvette of the Royal Navy of Oman
 * Ghafir, the 40th chapter of the Quran
 * Infiniti G-series (Q40/Q60), an automobile
 * Samsung Sens Q40, a laptop