How to Measure Penis with Ruler, Tape or String (No Tape Guide)
For length, always use a rigid plastic, wooden, or metal ruler placed along the top of the erect shaft, as flexible tapes tend to bend or slide and produce inaccurate results. For girth (thickness), use a soft tailor's tape measure, or if you do not have one, wrap a strip of paper or a non-stretchy piece of string around the mid-shaft, mark the overlap with a pen, and lay it flat against a standard ruler. Never use stretchy materials like rubber bands or dental floss, which warp when pulled. Measuring both dimensions with rigid or calibrated tools ensures your data matches clinical study standards.
Using a ruler for erect length correctly
Keep the ruler straight along the top curve of the erect penis. If you have an upward curve, follow the dorsal curve gently with a flexible ruler, but for most men, a straight rigid ruler gives the most reliable, reproducible number.
How to measure girth without a tape measure
Cut a strip of plain paper roughly half an inch wide. Wrap it around the middle of your erect shaft so it lies flat and snug. Mark the point where the paper overlaps with a sharp pencil, unroll it, and measure the distance between marks using a regular ruler.
Household items to avoid
Do not use construction tape measures (the sharp metal hook can pinch skin and add 1/8 inch of error) or elastic cords (which stretch when wrapped and under-report your girth by up to an inch).
My Size Report provides a private, calculator-led way to understand measurements against published research. Results are informational and should not be treated as medical advice.