The　plate　buckling　coefficient　is　controlled　by　the　web-flange　interaction　amongst　the　elements　comprising　the　cross　section,　and　influences　the　elastic　critical　stress　of　cross-section　(plate)　directly.　Based　on　classical　elastic　plate　buckling　theory　and　CUFSM　software,　the　relationship　between　buckling　coefficients　and　section　dimensions　is　investigated.　The　data　indicates　that　the　results　from　these　two　methods　are　mostly　consistent,　but　quite　different　in　some　special　cases.　These　facts　prove　that　the　CUFSM　software　has　limitation　in　calculating　elastic　local　buckling　loads.　The　simplified　formulas　of　buckling　coefficients　are　obtained　according　to　the　results　of　175　hot　rolled　sections.　Compared　with　other　current　solutions,　the　formulas　proposed　in　this　paper　can　achieve　more　accurate　predictions　and　can　be　used　in　Direct　Strength　Method　or　width-thickness　limits.　©　2017,　Engineering　Mechanics　Press.　All　right　reserved.