A rangefinder camera is one with a rangefinder that allows the photographer to judge the focusing distance. The rangefinder shows a double image, and lining up the two images of the object to be focused on more or less accurately gauges its distance. Older cameras may display the focusing distance and require the photographer to transfer the value to the lens focusing ring; most recent designs are coupled rangefinders - that is, the focus is adjusted both in the rangefinder and in the objective lens by the same control, very often a ring on the lens. In older designs the rangefinder is separate from the viewfinder; in newer ones it appears at the center of the viewfinder.

Rangefinder cameras were common from the 1930s to the 1970s, but the more advanced models lost ground to single-lens reflex (SLR) cameras.

The most famous rangefinder cameras take 135 film, employ focal-plane shutters, and have interchangeable lenses: these are Leica screwmount cameras (which gave rise to many imitations and derivatives), Zeiss Contax cameras, Nikon S-series cameras (inspired by the Contax), and Leica M-series cameras. All but the last succumbed in the marketplace to pressure from SLRs. The most recent in the M-series is the M7, which is the first of the series to feature automatic exposure.

There were also many well-built non-interchangeable lens rangefinder camera like the various Kodak Retina and Canon Canonet models. These camera were often designed as "compact cameras" or "compact rangefinders". They failed to compete with compact autofocus cameras.

There has been something of a revival of rangefinder cameras in the 1990s. Aside from the Leica M-series, current models include the Contax G1 and G2, the Konica RF, the Voigtländer Bessa R2, and the Hasselblad Xpan; Zeiss has also announced a new model. Cameras from the former Soviet Union -- the Zorki and FED, based on the screwmount Leica, and the Kiev, based on the classic Contax rangefinder -- are plentiful in the used market.

There are also medium-format rangefinder cameras, like the Mamiya 7, the Bronica RF645 and the Fuji G-series.

SLRs are usually more technically advanced than rangefinder cameras, with more system options, and have the advantage that the image is seen through the same lens through which it is photographed. Since the user looks through a viewfinder some distance from the lens and sees an image that is slightly different from the image which will be recorded on the film, framing becomes inaccurate at close range (parallax problem). However, more advanced rangefinder cameras project a frameline into the viewfinder which corrects parallax error at all but very close imaging distances. For close-up photography, the rangefinder camera is awkward to use, as the image recorded may be significantly different from what the viewer sees. Zoom lenses are not available for rangefinder cameras, though a very few lenses let the user select among two or three focal lengths. Rangefinder cameras do have several advantages over SLRs in certain applications. Since there is no moving mirror, as used in SLRs, the shutter response is faster and quieter and there is no momentary blackout; also, the camera's body is slimmer and less obtrusive. The lack of a mirror also allows lenses to project deep into the camera body, and so high quality wide-angle lenses are easier to design. (The Voigtländer 12mm lens is the widest-angle non-fisheye lens in general production.) In general, lenses are smaller than their SLR equivalents. The rangefinder focusing system is more accurate with standard and wide-angle lenses (whereas an SLR is more accurate with telephotos). The rangefinder focusing system is also faster and more accurate than manual focusing an SLR in low-light conditions. Since rangefinder cameras are simpler, they tend to be more durable - while some Leicas are collectors' items which are treasured and protected from the slightest scratch, they are nonetheless capable of withstanding considerable abuse and have been widely used by photojournalists. These qualities make rangefinders ideal for action-grabbing candid shots and street photography.