Observations considered for the atmospheric characterization of PSO J318. Uppermost panel: all data considered for the spectral characterization of PSO J318at the wavelength binning fed into the retrieval and self-consistent grid model fits. Specifically, MIRI MRS data was binned down to λ/Δλ = 400, while NIRSpec G395H was binned to λ/Δλ = 400 and λ/Δλ = 1000 for NRS1 and NRS2, respectively. Second panel: HST WFC3, IRTF SpeX, and JWST NIRSpec PRISM data over the 1–3 μm wavelength range. Third panel: JWST NIRSpec G395H data at the full spectral resolution. Lowermost panel: JWST MIRI MRS data at the full spectral resolution.