The value of acceleration due to gravity $g$ on the Earth's surface is:

Two effects combine to make $g$ slightly smaller at the equator than at the poles: 1. **Earth's shape.** Earth is an oblate spheroid; its diameter at the equator is about $42$ km larger than at the poles. Since $g \propto 1/R^2$ and equatorial $R$ is larger, $g$ is smaller there. 2. **Rotation.** Centrifugal effect from spinning reduces apparent gravity, maximally at the equator and zero at the poles. Typical values: $g_{\text{pole}} \approx 9.83$ m/s², $g_{\text{equator}} \approx 9.78$ m/s². Difference is small but real.