Abstract Objective The free gingival graft (FGG) has been identified as the most effective method for increasing keratinized mucosa width (KMW). However, the challenge emerges in cases of extensive keratinized mucosa deficiency, where efficient utilization of the patient's limited keratinized tissue to achieve optimal results is crucial. This article introduces a modified geometric technique to address this clinical issue. Clinical Considerations Utilizing geometric principles, the modified technique involves dividing the rectangular graft into two triangular or trapezoidal sections, which are then reassembled to form an approximate diamond shape. Through strategic cut and splice, the graft is reshaped to suit the recipient site. Conclusion Preliminary observations in cases employing the modified geometric technique have increased the KMW around implants. This method enhances graft utilization and offers a viable clinical option for surgical plans aimed at widening keratinized mucosa in instances of large‐area KMW deficiency. Clinical Significance This article proposed a modified method to increase KMW, which may be an optimal choice for patients with insufficient KMW in large area, avoiding the waste of limited graft, decreasing patient morbidity, and effectively widening keratinized mucosa.