CNC Machinist Calculator +
Speeds, Feeds, Taper & Tap
Only for iPhone
Free · Designed for iPhone. Not verified for macOS.
iPhone
Turning finish on Reference: feed 0.2 mm/rev and nose 0.8 mm read Ra 1.56 µm. Reverse to max feed for a target Ra.
CNC Machinist Calculator + puts the numbers a machinist reaches for all day into one shop app that works offline, in inches or millimetres.
SPEEDS & FEEDS
Pick a material and HSS or carbide, enter tool diameter, flute count and chip load, and read spindle RPM and table feed. Save presets for the tools you run most.
TAP DRILL
Metric and Unified (UNC/UNF) threads with an adjustable thread-engagement percentage. Shows the theoretical tap-drill size and the nearest standard drill.
BOLT CIRCLE
Hole count, diameter and start angle give X/Y coordinates for a bolt-hole pattern, ready to enter at the control.
TAPER
From two diameters and a length, or from an included angle, taper per foot or a 1:N ratio: compound-rest half-angle, included angle, taper per foot, taper per inch and ratio, shown in decimal degrees and degrees-minutes-seconds.
REFERENCE
Starting-point cutting speeds by material, a drill size chart (number, letter, fraction, metric), thread pitch and minor diameters, drill point depth factors and typical surface-finish ranges.
All values are conservative starting points from published data. Verify against your tooling and machine before cutting.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Turning surface-finish calculator on the Reference tab, under the taper card.
Verify: open Reference, scroll past Taper calculator to Turning surface finish. Leave mm selected. Mode Ra from feed. Enter feed 0.2 and nose 0.8 (or tap the 0.8 chip). Ra shows 1.563 µm and Rt 6.250 µm. Switch to Feed for Ra, enter target 1.6 with the same nose — max feed is 0.202 mm/rev. Caption states this is theoretical; real finish is typically 1.5–3× rougher. Feed at or above 2× nose radius blanks the numbers.
The developer, heekyung moon, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Used to Track You
The following data may be used to track you across apps and websites owned by other companies:
- Identifiers
- Usage Data
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- Identifiers
- Usage Data
- Diagnostics
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- heekyung moon
- Size
- 55.2 MB
- Category
- Utilities
- Compatibility
Requires iOS 16.4 or later.
- iPhone
Requires iOS 16.4 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
18+
- 18+
- Contains
Advertising
- Copyright
- © 2026 Moon