As a kid, these were called dungarees but now-a-days I call them workable blue jeans.  Not surprisingly, these jeans fit well (true waist to size chart; but for the length part, well, mine where a bit longer than a 30" inseam).  However they are made out of strong cloth and holds-up after several washing and the jeans look good too!  These may become my favorite workable-jeans for the comfort-ability.