Background: Diabetic foot ulcers are associated with infection, impaired perfusion, delayed healing, and lower-extremity amputation. The Society for Vascular Surgery Wound, Ischemia, and foot Infection (WIfI) classification and the International Working Group on the Diabetic Foot Perfusion, Extent, Depth, Infection, and Sensation (PEDIS) score assess different dimensions of limb threat. This study compared their diagnostic performance for 12-month amputation. Methods: A retrospective diagnostic accuracy study included 72 patients with diabetic foot ulcers treated at H. Adam Malik General Hospital, Medan, Indonesia, from January 2023 to December 2024. Baseline WIfI stage and total PEDIS score were reconstructed from medical records, and amputation during treatment or follow-up within 12 months was the reference outcome. Receiver operating characteristic analysis identified optimal thresholds using the Youden index. Sensitivity, specificity, predictive values, accuracy, and relative risk were calculated. Results: Amputation occurred in 57 patients (79.2%). WIfI stages 3-4 were present in 51/57 patients who underwent amputation and 5/15 who did not; high PEDIS scores (8-12) were present in 47/57 and 2/15, respectively (both p<0.001). The area under the curve was 0.861 (95% CI 0.764-0.958) for WIfI stage and 0.846 (95% CI 0.742-0.950) for PEDIS. At WIfI stage >=3, sensitivity was 89.5%, specificity 66.7%, and accuracy 84.7%. At PEDIS >=8, sensitivity was 82.5%, specificity 86.7%, and accuracy 83.3%. Conclusion: Both systems showed good discrimination. WIfI stage was more sensitive and may be preferable for initial screening of limb threat, whereas PEDIS was more specific and had a higher positive predictive value. A formal paired comparison of the two AUCs and external prospective validation are required before declaring one system superior.