A T-square is a technical drawing instrument used by draftsmen primarily as a guide for drawing horizontal lines on a drafting table. It may also guide a set square to draw vertical or diagonal lines. Its name comes from its resemblance to the letter T. T-squares come in varying sizes, common lengths being , , , and .

T-square may be

• T-square, the drafting and technical drawing tool
• T-square (fractal), in mathematics, a two dimensional fractal
• T-Square (software), the early drafting software program
• T-Square (band), Japanese jazz fusion band
• A variation of grand cross in astrology
• T-square position, a sexual position
• Tom "Tsquared" Taylor, professional Halo player

A T-square is a technical drawing instrument used by draftsmen primarily as a guide for drawing horizontal lines on a drafting table. It may also guide a set square to draw vertical or diagonal lines. Its name comes from its resemblance to the letter T. T-squares come in varying sizes, common lengths being , , , and .

T-square may be

• T-square, the drafting and technical drawing tool
• T-square (fractal), in mathematics, a two dimensional fractal
• T-Square (software), the early drafting software program
• T-Square (band), Japanese jazz fusion band
• A variation of grand cross in astrology
• T-square position, a sexual position
• Tom "Tsquared" Taylor, professional Halo player