Global empirical models for infrasonic signal celerity (the epicentral distance divided by the total travel time) and backazimuth deviation (the difference between the measured and predicted backazimuth assuming great circle propagation), are used for the association of infrasound automatic detections, event location and acoustic propagation simulation validation. Following a previous methodology to develop a regional celerity-range model (Nippress et al., 2014), we developed a software suite for consistent analysis of a global ground truth database, allowing estimation of empirical models for celerity and backazimuth. We observe 304 detections in the 0.32–1.28 Hz passband, with propagation path lengths of between 25 and 6280 km. Models derived from these observations suggest the backazimuth deviation distribution is range-independent, 92% of the detections studied have a deviation ≤ ±5º. However, the celerity model, produced through fitting the travel-times with a linear regression model, is range-dependent. The celerity model bounds are determined using a quantile regression fit to the travel-time residuals, and are consistent with the current understanding of infrasound propagation. At 10 + years since the publication of the last global celerity-range model, this study provides a timely update.UK Ministry of Defence © Crown Owned Copyright 2022/AWE