A simple, largely empirical but physically motivated model is presented to interpret the mid- and far-infrared spectral energy distributions (SEDs) of galaxies consistently with ultraviolet (UV), optical, and near-infrared (NIR) emission. The model uses an existing angle-averaged prescription to compute the absorption of starlight by dust in stellar birth clouds and the ambient interstellar medium (ISM). The SED of dust re-radiated in stellar birth clouds is composed of three components: polycyclic aromatic hydrocarbons (PAHs), a mid-infrared continuum from hot grains (130–250 K), and grains in thermal equilibrium (30–60 K). In the ambient ISM, the relative proportions of these components are fixed to match the diffuse cirrus emission in the Milky Way, with an additional component of cold grains (15–25 K). The model is versatile and can be used to derive statistical constraints on star formation histories and dust contents of large galaxy samples using UV, optical, and infrared observations. It is applied to 66 nearby star-forming galaxies from the Spitzer Infrared Nearby Galaxy Survey (SINGS), yielding median likelihood estimates of star formation rates, stellar masses, effective dust optical depths, dust masses, and dust component strengths. The model shows that mid- and far-infrared colours of galaxies strongly correlate with the specific star formation rate and other galaxy-wide quantities related to it, such as the ratio of infrared luminosity between stellar birth clouds and the ambient ISM, contributions by PAHs and grains in thermal equilibrium to total infrared emission, and the ratio of dust mass to stellar mass. The model is applied to interpret UV, optical, and infrared SEDs of any galaxy sample.A simple, largely empirical but physically motivated model is presented to interpret the mid- and far-infrared spectral energy distributions (SEDs) of galaxies consistently with ultraviolet (UV), optical, and near-infrared (NIR) emission. The model uses an existing angle-averaged prescription to compute the absorption of starlight by dust in stellar birth clouds and the ambient interstellar medium (ISM). The SED of dust re-radiated in stellar birth clouds is composed of three components: polycyclic aromatic hydrocarbons (PAHs), a mid-infrared continuum from hot grains (130–250 K), and grains in thermal equilibrium (30–60 K). In the ambient ISM, the relative proportions of these components are fixed to match the diffuse cirrus emission in the Milky Way, with an additional component of cold grains (15–25 K). The model is versatile and can be used to derive statistical constraints on star formation histories and dust contents of large galaxy samples using UV, optical, and infrared observations. It is applied to 66 nearby star-forming galaxies from the Spitzer Infrared Nearby Galaxy Survey (SINGS), yielding median likelihood estimates of star formation rates, stellar masses, effective dust optical depths, dust masses, and dust component strengths. The model shows that mid- and far-infrared colours of galaxies strongly correlate with the specific star formation rate and other galaxy-wide quantities related to it, such as the ratio of infrared luminosity between stellar birth clouds and the ambient ISM, contributions by PAHs and grains in thermal equilibrium to total infrared emission, and the ratio of dust mass to stellar mass. The model is applied to interpret UV, optical, and infrared SEDs of any galaxy sample.