A CNC programmer looking for work in the United States may have to decide which CAM system to learn next. Both Mastercam and Siemens NX appear in job ads, but employers name them at different rates and for different work. Posting data helps with the first question; the responsibilities in each opening explain the second.
What the job-posting data shows
In the O*NET in-demand software table for U.S. Computer Numerically Controlled Tool Programmers, Mastercam appears in 35% of unique postings from 2025. The table uses Lightcast posting data. Siemens NX does not appear among the six software skills displayed. If the goal is to keep a broad range of CNC programming jobs open, this is a strong reason to consider Mastercam first.
That 35% needs a careful reading. O*NET groups ads under an occupational category; it does not manually select only jobs titled CNC Programmer. The percentage counts postings that explicitly name the skill. It says nothing about shops that use Mastercam without naming it in an ad. The displayed table also provides no exact percentage for NX, and the figure should not be described as a share of all CNC programming jobs.
Where NX appears
NX remains relevant to particular employers. A Boeing posting for an NC programmer in its Spirit Defense business, for example, lists NX alongside CATIA and Vericut among preferred tools. The role includes reviewing engineering models, validating NC programs, and working with engineering and manufacturing teams. This tells us about that opening; it does not establish which software dominates aerospace as a whole.
In these jobs, the employer may care about how a programmer takes a product model through manufacturing preparation, revisions, and program verification. NX CAM combines CAD and CAM tools, supports geometry preparation, and provides toolpath verification within the engineering environment. Knowing its interface still has to be backed by sound choices about datums, tooling, and a safe machining sequence.
Read software names carefully. Siemens NX CAM is a system for preparing machining programs. Siemens Sinumerik is a family of machine controls. An ad mentioning Sinumerik does not automatically require NX CAM experience.
What an employer may accept
A named CAM package can be a firm requirement, a preference, or one example of suitable experience. A shop may need Mastercam experience because the new hire will immediately maintain its existing programs and postprocessors. Another employer may accept NX, hyperMILL, or Mastercam if the applicant can program the required machine type. Read the full description of the work before treating one software name as the whole requirement.
Much of the underlying work transfers: interpreting the drawing and model, planning setups, choosing tools and cutting parameters, verifying toolpaths, posting code for the machine, and checking the first part. Changing CAM systems still means learning a new interface, libraries, and company procedures. It does not erase machining experience.
Choosing what to learn
For a job search that is not tied to a particular employer, Mastercam is a practical first choice based on the available posting data. Someone targeting companies that name NX should get hands-on with NX CAM itself: program a small part, build the operations, verify the paths, and explain how the posted code relates to the machine and postprocessor.
Before committing to a course, collect a few dozen openings in the target region and machining specialty. Mark which skills are required or preferred, the number of axes, milling or turning work, setup duties, and any named controls. That local sample can guide the next step better than a national software ranking, particularly for someone who already knows one CAM system and is considering a second.
In the national O*NET table, Mastercam is much more visible among named software skills for CNC tool programmers. NX appears in individual engineering and production roles where experience with that particular system may matter. The useful training decision starts with the kind of job and employer you want, followed by a close reading of their CAM requirements.