Assessing drilling and rig operations performance are a cumbersome issue for oil operators. The evaluation of effectiveness of drilling operations and safe, environmental and competent manner is drilling scenarios such depths, formation lithology, drilling proximity, directional plan complexity and completion types. In this paper a new a new firm methodology improves rig performance is implemented during drilling operations. The method strongly depends on monitoring drilling time and dead time. Drilling time or rotating time and dead time or non-productive time will assessed during drilling operations to predict the rig performance and hence evaluate which performance of drilling rigs has the highest ratio. The ration is based on the drilling time (Tdrilling) over dead time (Tdead) for evaluating rig efficiency. The methodology can compare performance in different scenarios under variable condition with difficult uncertainties. That will lead to utilize the provided resources by oil operators effectively. Several procedures and tactics were developed earlier to evaluate the rig efficiency regarding drilling rate, hole cleaning and rig operations effectiveness, however, they lack for practicality in fields, not applicable in all drilling scenarios, high cost & time impact. Many offset data for rotating time and non-productive time were collected to analysis and monitor the performance of rigs to come up with best estimate of rig performance indicator (RPI) by using technical limit ratio (TLR). The TLR uses, rate of penetration (ROP), Hole cleaning performance (HCP) and rig matrix to finally develop RPI which is ratio that combines ( rotating time plus lost time during drilling over ( dead time plus lost time during rig operations. RPI contains time drilling, rig operations, coring, tripping, completion, blowout preventer equipment (BOPE) nippileing and wellhead work. This is the first time to develop RPI to utilize and evaluate the performance efficiently in real time and was deployed in filed operations. RPI showed recognized improvement in rig efficiency by 50%. Hence, it ca be run in a real-time operating center (RTOC) for meeting fourth industrial revolution for drilling automations. It an effective tool for drilling team to allow immediate evaluation and monitoring for optimizing rig performance