field code
Short answer
A dynamic text expression inside AutoCAD text or block attribute that auto-evaluates from a drawing property, date, file path, or formula.
A field is an AutoCAD text token that evaluates to a live value — current date, drawing filename, object's area, a system variable. Fields show on screen with a grey background and update on REGEN or save. Sheet title blocks rely on fields to pull project numbers and revision dates without manual edits. Custom fields can also reference user-defined properties through the FIELD command's Diesel expressions.