Lookahead heuristics are algorithmic search and decision-making strategies that estimate future costs, rewards, or constraint satisfaction by evaluating potential downstream states beyond the immediate next step. Drawing foundational principles from informed search methods such as A-star search, these heuristics provide predictive evaluations that guide intermediate choices toward paths most likely to produce valid, globally optimal, or goal-compliant outcomes. In computational fields such as automated planning, graph search, and sequential text generation, lookahead heuristics allow decoding and exploration procedures to anticipate downstream requirements, helping systems avoid dead ends, adhere to complex logical constraints, and balance computational efficiency with foresighted path selection.