The Toyota iQ is a city car manufactured by Toyota and marketed in a single generation for Japan (2008–2016); Europe (2008–2015); and North America (2012–2015), where it was marketed as the Scion iQ. A rebadged variant was marketed in Europe as the Aston Martin Cygnet (2011–2013).

Designed at the Toyota European Design and Development studio in Nice, France, the iQ is noted for its specialized engineering to maximize passenger space and minimize length. The design accommodates four occupants.

Following a concept presented at the 2007 Frankfurt Motor Show, the production iQ debuted at the March 2008 Geneva Motor Show. Japanese sales began in November 2008 and European sales in January 2009. In 2008, the iQ was named the Japanese Car of the Year.

The name iQ, an initialism of the term intelligence quotient, recalls a competitor, the Smart Fortwo. The letters "iQ" also stand for "individuality", "innovation", "quality", a hint at its "cubic form" and also a "cue" for owners to embrace new types of vehicles and lifestyles.

The iQ reached the end of production in December 2015, and it was discontinued in Japan in April 2016.^{[citation needed]}

The IQ design emphasizes fuel efficiency, maneuverability, low environmental impact, and interior space. Six design factors enable the minimal overhangs, forward windscreen location, maximized cabin space and overall compactness:

The iQ features a transmissions differential housing located ahead of, rather than behind, the engine; a starter motor incorporated in the engine's flywheel, a high-mounted steering rack and a compact, high-located air conditioning unit behind the dashboard central area. The arrangement allows the front passenger to sit forward of the driver, giving increased rear passenger legroom. A shallow under-floor fuel tank reduces rear overhang.

Because of its overall width and engine displacement, the iQ is classified in its home market as a supermini, though its length complies with kei car dimensional regulations.