Reliable ozone spectral data consistent over several spectral ranges are a challenge for both experiment and theory. We present ab initio calculations for strong lines that lead to consistent results from the microwave to mid-infrared regions. The results agree well with established microwave line lists and our new measurements in the fundamental and first overtone regions of ozone at 5 and 10 μm. The calculations and their agreement to within 1% with measurements provide an important step toward consistent and accurate spectroscopic ozone data. The results imply that actual databases need to be corrected by about 3% in the corresponding mid-infrared spectral intervals. Appropriate recommendations for the consistency of strong line intensities of the ozone molecule in microwave, 10 and 5 μm ranges, in HITRAN (HIgh-resolution TRANsmittance and molecular apbsorption) and GEISA (Gestion et Etude des Informations Spectroscopiques Atmosphériques) databases are suggested. I. INTRODUCTION