When bending a 90 do you add or subtract?

When bending a 90 you subtract. Measure the stub you need, subtract your bender's take-up, 5 inches for half inch EMT, 6 for three quarter, 8 for 1 inch, mark there, and bend with the arrow on the mark.

Adding shows up in one place: some back-to-back techniques measure from the finished first bend and add to locate the second mark using the star point. That method difference is where the add-or-subtract confusion is born.

Offsets neither add nor subtract; they multiply, obstacle depth times the angle's multiplier, then the run shrinks slightly toward you.

Whichever method, consistency wins; mixing measurement systems mid-run is how stubs miss by an inch.

The bend multiplier calculator keeps deducts, multipliers, and shrink straight for every angle.