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<p>A fast pseudo-monochromatic radiative transfer package using a singular value decomposition (SVD) compressed atmospheric optical depth database has been developed, primarily for simulating radiances from hyperspectral sounding instruments (resolution <span class="inline-formula">≥0.1</span>&thinsp;cm<span class="inline-formula">⁻¹</span>). The package has been tested extensively for clear-sky radiative transfer cases, using field campaign data and satellite instrument data. The current database uses HITRAN 2016 line parameters and is primed for use in the spectral region spanning 605 to 2830&thinsp;cm<span class="inline-formula">⁻¹</span>. Optical depths for other spectral regions (15–605 and 2830–45&thinsp;000&thinsp;cm<span class="inline-formula">⁻¹</span>) can also be generated for use by kCARTA. The clear-sky radiative transfer model computes the background thermal radiation quickly and accurately using a layer-varying diffusivity angle at each spectral point; it takes less than 30&thinsp;s (on a 2.8&thinsp;GHz core using four threads) to complete a radiance calculation spanning the infrared. The code can also compute non-local thermodynamic equilibrium effects for the 4&thinsp;<span class="inline-formula">µ</span>m <span class="inline-formula">CO₂</span> region, as well as analytic temperature, gas and surface Jacobians. The package also includes flux and heating rate calculations and an interface to an infrared scattering model.</p>