We report on the dynamic properties of Permalloy nanostrips at gagahertz frequencies. The thickness of the strips is 100 nm, strip width is 300 nm, strip spacing is 1 m, and length is 0.3-100 m; aspect ratios are 1:1, 1:2, 1:3, 1:5, 1:10, and 1:333. The dynamic behavior was studied by network analyzer ferromagnetic resonance ͑FMR͒ using Permalloy strips on a coplanar waveguide in flip-chip geometry. The FMR mode frequencies ͑f r ͒ can be controlled by the aspect ratio as well as by the applied magnetic field ͑H͒. In longer strips ͑1:10 and 1:333͒, the excitation frequencies show a soft mode behavior ͑H eff = 990 Oe͒ when the field is along the hard axis. However, along the easy axis ͑along the strip length͒, f r increases with applied field. At a field of 3 kOe, f r values are almost independent of aspect ratio along the easy axis except for the 1:1 strip. Along the hard axis, the frequencies are strongly dependent upon the aspect ratio. We also observed that the frequency linewidths of the strips are dependent on the aspect ratio.