Calculators
Calculators a machinist or engineer actually bookmarks
Each calculator does one job with the math shown: the formula, the units, the assumptions and the starting values to adjust. Run the numbers, then send the part to a U.S. shop that fits it.
11 calculators, free, no sign-in.
Machining
Speeds & feeds calculator
RPM and feed rate for milling, turning and drilling, with chip thinning, a machine RPM limit and starting values by material.
Machining time calculator
Cycle time per part and per lot from length of cut, feed and passes, plus rapids, tool changes, setup and machine cost.
CNC cost estimator
A ballpark price for a machined or fabricated part from size, material, process and quantity.
Sheet metal
Bend allowance calculator
Bend allowance, bend deduction and flat-pattern length from thickness, inside radius, angle and K-factor.
Press brake tonnage calculator
Air-bend tonnage from thickness, V-die and material, plus the radius it forms and the shortest flange.
Sheet nesting calculator
How many rectangular blanks fit on a sheet, how many sheets a run needs, and how much ends up as scrap.
Mechanical design
Fit tolerance calculator
ISO 286 hole and shaft limits for any fit, with clearance or interference and the preferred-fit presets.
Tolerance stack-up calculator
A 1D stack-up with worst-case and RSS results, and which dimension drives the variation.
Bolt circle calculator
X/Y coordinates for any number of holes on a bolt circle, with start angle, center offset and hole spacing.
Thermal expansion calculator
Length and diameter change from CTE and temperature, a CTE table for metals and plastics, and a shrink-fit helper.
Material and weight
Metal weight calculator
Weight of bar, plate, sheet, tube and pipe in steel, stainless, aluminum, brass, copper and titanium.
