A modern gouge is similar to a chisel except its blade edge is not flat, but instead is curved or angled in cross-section. The modern version is generally hafted inline, the blade and handle typically having the same long axis. If the bevel of the blade is on the outer surface of the curve the gouge is called an 'out-cannel' gouge, otherwise, it is known as an 'in cannel' gouge. Gouges with angled rather than curved blades are often called 'V-gouges' or 'vee-parting tools'.
The blade geometry is defined by a semi-standardized numbering system that varies by manufacturer and country of origin. For each gouge a "sweep number" is specified that expresses the part of a circle defined by the curve of the blade. The sweep number usually ranges from #1, or flat, up to #9, a semi-circle, with additional specialized gouges at higher numbers, such as the U-shaped #11, and a v-tool or parting tool, which may be an even higher number such as #41. In addition to sweep, gouges are also specified by the distance from one edge of the blade to the other (this corresponds to the chord of the circle section defined by the edge of the blade). Putting these pieces together, two numbers are used to specify the shape of the cutting edge of a gouge, such as a '#7-20mm'. Some manufacturers provide charts with the sweeps of their blades shown graphically.
In addition to varying blade sweeps, bevels, and widths, blade variations include:
'Crank-neck' gouges, in which the blade is offset from the handle by a small distance, to allow working flat to a surface
'Spoon-bent' gouges, in which the blade is curved along its length, to allow working in a hollow not otherwise accessible with a straight bladed gouge
'Fishtail' gouges, in which the blade is very narrow for most of its length and then broadens out near the working edge, to allow working in tight spaces.
All of these specialized gouges allow a craftsperson to cut into areas that may not be possible with a regular, straight-bladed gouge.
The cutting shape of a gouge may also be held in an adze, roughly as the shape of a modern-day mattock.
Gouges are used in woodworking and arts. For example, a violin luthier uses gouges to carve the violin, a cabinetmaker may use it for running flutes or paring curves, or an artist may produce a piece of art by cutting some bits out of a sheet of linoleum (see also Linocut).
Gouges were found at a number of historic Bronze Age hoards found in Great Britain.