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A key point of landslide hazard assessment is the estimation of their runout. Empirical relations linking angle of reach to volume can be used relatively easily, but they are generally associated with large uncertainties as they do not consider the topographic specificity of a given study site. On the contrary, numerical simulations provide more detailed results on the deposits morphology, but their rheological parameters can be difficult to constrain. Simulating all possible values can be time consuming and incompatible with operational requirements of rapid estimations. We propose and compare three operational methods to derive scaling power laws relating the landslide travel distance to the destabilized volume. The first one relies only on empirical relations, the second one on numerical simulations with back-analysis, and the third one combines both approaches. Their efficiency is tested on three case studies: the Samperre cliff collapses in Martinique, Lesser Antilles (0.5 to <inline-formula><math display="inline"><semantics><mrow><mn>4</mn><mo>×</mo><msup><mn>10</mn><mn>6</mn></msup></mrow></semantics></math></inline-formula> m<inline-formula><math display="inline"><semantics><msup><mrow></mrow><mn>3</mn></msup></semantics></math></inline-formula>), the Frank Slide rock avalanche (<inline-formula><math display="inline"><semantics><mrow><mn>36</mn><mo>×</mo><msup><mn>10</mn><mn>6</mn></msup></mrow></semantics></math></inline-formula> m<inline-formula><math display="inline"><semantics><msup><mrow></mrow><mn>3</mn></msup></semantics></math></inline-formula>) and the Samperre cliff collapses in Martinique, Lesser Antilles (0.5 to <inline-formula><math display="inline"><semantics><mrow><mn>4</mn><mo>×</mo><msup><mn>10</mn><mn>6</mn></msup></mrow></semantics></math></inline-formula> m<inline-formula><math display="inline"><semantics><msup><mrow></mrow><mn>3</mn></msup></semantics></math></inline-formula>) the Fei Tsui debris slide in Hong Kong (<inline-formula><math display="inline"><semantics><mrow><mn>0.014</mn><mo>×</mo><msup><mn>10</mn><mn>6</mn></msup></mrow></semantics></math></inline-formula> m<inline-formula><math display="inline"><semantics><msup><mrow></mrow><mn>3</mn></msup></semantics></math></inline-formula>). Purely numerical estimations yield the smallest uncertainty, but the uncertainty on rheological parameters is difficult to quantify. Combining numerical and empirical approaches allows to reduce the uncertainty of estimation by up to 50%, in comparison to purely empirical estimations. However, it may also induces a bias in the estimation, though observations always lie in the 95% prediction intervals. We also show that empirical estimations fail to model properly the dependence between volume and travel distance, particularly for small landslides (<20,000 <inline-formula><math display="inline"><semantics><mrow><mo><</mo><mn>0.02</mn><mo>×</mo><msup><mn>10</mn><mn>6</mn></msup></mrow></semantics></math></inline-formula> m<inline-formula><math display="inline"><semantics><msup><mrow></mrow><mn>3</mn></msup></semantics></math></inline-formula>).