Online RulerEstimate Cable Width
Measure straight across the outside of the cable at a point where its shape looks typical. Use a calibrated AR Ruler screen or a printed scale. Let the cable rest in its usual shape and read from one outer edge to the other. For a flat cable, lay the broad face down to measure its width.
- Measure across the cable at a right angle to its length.
- The reading includes the outer covering. The cable body and any raised sleeve or connector have their own widths.
- A soft cable can flatten under pressure, so let it rest while you line up the edges.
- Pick a straight stretch of cable away from a bend, raised marking, sleeve, or connector. If one of those features is the part you need to measure, place the ruler at that point instead.
- Open AR Ruler and choose centimeters or fractional inches. Verify the screen scale against the bank card used for calibration. If you use the printable page, check the test line with a physical ruler before taking a reading.
- Lay the cable across the scale with one edge at zero on the screen or on paper. On screen, move the marker to the opposite edge. On paper, leave enough of the scale visible to read that edge.
- Look straight down and read the far edge. Repeat nearby on the same stretch. If the width varies, keep the readings as a range and write down where you measured.
Round and flat cable
For a round cable, the outside span across the body is its approximate outside diameter. Read the widest visible part while looking down. A flat cable has a broad face and a narrow edge. Lay it on its broad face to read the width. If you need its thickness too, take a separate reading with the narrow edge facing up.
Keep the edge visible
A rounded cable can cast a shadow next to the scale. Use the boundary of the covering as the edge. Shift the light if the boundary is hard to see. If the cable rolls while you move the marker, steady it farther down its length so your fingers leave the measuring point clear.
Use a paper scale
The AR Ruler print page has a 15 cm scale and a 6 in scale. Print at actual size and compare the 10 cm test line with a physical ruler. After the check, place the sheet on a firm surface. Keep it flat while you align the cable across the scale.
Should I include the sleeve near the end?
Measure the plain body for the cable width. Measure the sleeve separately if that is the part you need to size.
What if the cable looks oval?
Turn it gently and take readings across its widest and narrowest faces. Label both so you can tell them apart later.
What if the edge falls between marks?
Write down the nearest mark and label it approximate. If you can see a clear gap on both sides, note the two marks that bracket the edge.