i dont see keft adjustment in burn display.is normal?
Technically, Kerf is the width of the cutting tool - laser or saw or endmill, no matter. You are correct that we use kerf in LightBurn and Stock to Leave in MillMage, however.
Typically you donāt use kerf adjustment in MM - You specify the tool to use, and whether youāre cutting inside or outside the line. In those cases the kerf offset is automatic.
i though i was in the laser software
@dan522, yes, correct, and sorry for that. 
This was posted in our MillMage section of the forum, so that may have caused some confusion. I can help fix that by first moving this to our LightBurn section, and then Iāll answer your question.
Kerf Offset settings are controlled in the LightBurn āCut Settings Editorā, under the āCommonā tab.
Are you saying you have entered a Kerf Offset value but are not seeing that applied when you run or Preview the job? Below I show the setting and results of applying a -5 mm kerf offset to a 20 x 20 mm rectangle.
Make sure you donāt have beginner mode active. If you do, Kerf would be hidden as that is a more advanced feature.
In general, posting a screen shot along with a question like this would avoid a ton of back and forth and confusion.
If you said, āIām expecting to see the kerf value here on this screenā and provided a screen shot that had ābeginner modeā in the title, for example, weād know immediately what was wrong. Ditto if it showed a Fill layer instead of Line mode, etc.