Inputs stay local
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Browser-local shop utilities / Rev. 01
Machining math.
Known inputs.
Visible assumptions.
Practical calculators for feeds, speeds, threads, coordinates, tolerances, and process setup—built to show the math close to the result.
- PROCESSING
- On this device
- COST
- Free to use
- OUTPUT
- Verify at machine
FEATURED / 01
Set the spindle with the diameter in view.
Start with the most common shop calculation. Switch between RPM and cutting speed without sending a value off the page.
OUTPUT
READYEnter known values and calculate.
Results stay on this device.CALCULATOR INDEX
One operation at a time.
Every calculator has a dedicated reference page with the formula, expected units, assumptions, and task-specific warnings.
- 01Feeds & speedsSpindle speed
Calculate spindle RPM from cutting speed and diameter, or convert RPM back to surface speed in metric or inch units.
↗ - 02Feeds & speedsFeed & chip load
Calculate milling feed rate or chip load from spindle RPM, cutting edges, and feed per tooth in metric or inch units.
↗ - 03Process planningMaterial removal
Calculate milling material removal rate from width of cut, depth of cut, and feed rate in metric or inch units.
↗ - 04ThreadsTap drill size
Estimate tap drill diameter from thread major diameter, pitch or TPI, and desired thread engagement for metric and inch threads.
↗ - 05ThreadsPitch ↔ TPI
Convert thread pitch in millimetres to threads per inch, or TPI to metric and inch pitch with exact spacing math.
↗ - 06CoordinatesBolt circle coordinates
Generate equally spaced X and Y hole coordinates from bolt circle diameter, hole count, start angle, center, and direction.
↗ - 07GeometryChamfer & countersink
Calculate axial depth or large diameter for a straight conical chamfer or countersink from diameters and included angle.
↗ - 08ToleranceTolerance stack-up
Calculate nominal, worst-case, and root-sum-square tolerance stack ranges from asymmetric dimension tolerances.
↗ - 09TurningTurning finish
Estimate theoretical turning surface roughness Ra and Rt from feed per revolution and tool nose radius in metric or inch units.
↗ - 10Process setupCoolant mixing
Calculate concentrate and starting-liquid volumes needed to reach a target coolant concentration in litres or gallons.
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WORKING PRINCIPLES
A calculator is a check, not a process plan.
Units stay visible
Selections and output units remain beside the values to reduce ambiguous conversions.
Limits stay attached
Each tool states what the formula assumes and where machine, tooling, material, or standards data must take over.