To develop equations to predict therapeutic continuous positive airway pressure (CPAPT) based on home-based CPAP titration, including the type of interface used. Retrospective study conducted in adult patients with obstructive sleep apnea (OSA) who used home-based autoCPAP titration (AutoSet S10, ResMed®). CPAPT was obtained manually through a visual analysis of autoCPAP data (CPAPV) and automatically using the 95th percentile pressure (CPAPP95). Multiple linear regression and K-fold cross-validation were applied. Independent variables were AHI, neck circumference (NC), BMI, and mask. Two formulas were generated based on mask and the Miljeteig and Hoffstein formula. We included 702 patients (174 women), median age, BMI and AHI of 58 years, 32kg/m2 and 32 ev/h, respectively. Predictors for CPAPv (M1) were BMI, NC, AHI and type of interface (R2: 0.19); and for CPAPP95 (M2), BMI, AHI and mask (R2: 0.09). Error and precision between the formulas and CPAPT were: 0 (CPAPV/CPAPP95), and - 3.2 to 3.2 (CPAPV) and - 4 to 4cm H2O (CPAPP95). CPAPV was higher with oronasal mask (10 vs. 9cm H2O, p < 0.01). Accuracy defined as; a difference ± 2 cm H2O between estimated CPAP and CPAPT was greater in M1 than in M2 (79% vs. 64%, p < 0.01). In both models, calculated error was close to zero. CPAPV (± 3.2cm H2O) showed more precision than CPAPP95 (± 4cm H2O). With M1 (CPAPV), 79% of patients could start CPAP with reasonable accuracy (error of ± 2cm H2O).