There are lots of measuring tools that you can use. Some are specific to sewing and others are used for household projects.
Sewing Gauge - Measure hem depth and seam width. You can purchase one or make your own on Fearless Makers.
Ruler 12” / 30cm- Draw lines and measure.
Short Ruler 6” / 15cm - Draw lines and measure.
Sewing Tape Measure – Measure body and objects.
Flexible Ruler – Bendable ruler for measuring arcs (armhole, crotch depth, neckline, etc).
Design Ruler – Use for french curves, hip curve, straight ruler and cut-out slots. Good for pattern alterations.
Triangle – Square corners, draw lines.
T-Square – Square corners, draw lines
Metal Ruler 12”- 48” / 30 - 122cm - Draw lines, measure fabric. (Called straight edge ruler at home improvement stores).
Retractable Metal Tape Measure – Measure windows, furniture and large projects.
Carpenter's/Framing Square – Square corners, draw lines. (Home improvement store find.)
Retractable Sewing Tape Measure – Measure body and objects.
Templates – Draw perfect circles or other shapes.
Compass – Add seam allowance or other distance to circles
Yard Stick – Measure fabric and heights. Don't buy wood!
Retractable Circumference Tape – Measure girth, circular tape.