About WebMachinist.Net
A free machinist calculator and shop reference site, independent and under new ownership.
What this site covers
WebMachinist.Net covers nine areas: speeds and feeds, holemaking and tapping, threading, inspection and GD&T, layout and shop math, CNC programming and alarms, manual machining, tooling and hardware reference, and shop power. Every calculator and chart is free. There are no accounts, no signup and no paywall.
Who runs it
WebMachinist is an independent, privately held site under new ownership. Pages publish under the site name, without bylines.
Where the numbers come from
Every formula and table value cites its source: Machinery's Handbook, the governing ASME, ANSI, ISO or NEC standard, or the tool maker's published data. We summarize and cite standards rather than reproduce their tables. Rules of thumb are labeled as rules of thumb, with the range.
Pages that show "Technical review pending" under the title already cite their formulas and values. The notice comes down after a machinist review.
Results are starting points
Calculator results are starting points. Check them against your drawing, machine, tooling and material before you cut. Tool-maker charts assume a rigid machine; on a light hobby machine, start at the low end and adjust by sound and chip.
Corrections
If you find an error, send the page URL and the values you entered to editor@webmachinist.net. Confirmed errors get fixed, and the page's "Last updated" date changes.
Printing
Every chart has a print-friendly version. Use the "Print this chart" button above the table, or your browser's print command on any page.
History
The site first went online around 2013 and relaunched under new ownership in 2026. Nothing was copied over: every page, table and calculator was rebuilt from scratch against published sources. The old URLs still work.
Looking for the old software?
WebMachinist.Net is not the Web Machinist software company and sells no software or apps. The former Web Machinist Windows software and its Android apps are not connected to this site and are not supported here, as the page on the old software explains.
Contact
Email editor@webmachinist.net. The contact page has the details.
Last updated