Two-dimensional magnets have emerged as a promising platform for nanoscale spintronics and solid-state refrigeration. In this work, we investigate the magnetic phase transitions and magnetocaloric properties of monolayer $\mathrm{AlCr}{X}_3$ $(X=\mathrm{Se}, \mathrm{Te})$ using density functional theory calculations and spin dynamics simulations, with the consideration of exchange interaction (J), anisotropic energy (K), and Dzyaloshinskii–Moriya interaction (D). It is found that ${\mathrm{AlCrSe}}_3$ presents a labyrinth-like (LL) spin texture, while ${\mathrm{AlCrTe}}_3$ manifests a spin-spiral (SS) phase characterized by the coexistence of labyrinthine domains and skyrmions. Sizeable magnetocaloric effects (MCE) are observed; the magnetic entropy change of ${\mathrm{AlCrSe}}_3$ $\left(5.1\mu \mathrm{J}{\mathrm{m}}^{-2}{\mathrm{K}}^{-1}\right)$ is 2.5 times that of ${\mathrm{AlCrTe}}_3$ $\left(2\mu \mathrm{J}{\mathrm{m}}^{-2}{\mathrm{K}}^{-1}\right)$. Interestingly, the stronger D in ${\mathrm{AlCrTe}}_3$ facilitates a remarkable inverse magnetocaloric effect (IMCE) with an entropy change of $21\mu \mathrm{J}{\mathrm{m}}^{-2}{\mathrm{K}}^{-1}$, which is absent in ${\mathrm{AlCrSe}}_3$. A one-dimensional spin-chain model is proposed to elucidate the direct relationship between the spin deflection angle and the D/J ratio, serving as a mechanistic descriptor to clarify the microscopic origin of potential IMCE materials. In addition, we present a magnetic-state evolution map, determined by specific quantitative criteria, to analyze the thermodynamic responses across different transition regions. The present work highlights the pivotal role of Dzyaloshinskii–Moriya-interaction-mediated spin-texture evolution in modulating the thermal response of 2D magnets and provides theoretical guidance for the design of next-generation nanoscale refrigeration devices.

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• Dzyaloshinskii-Moriya interaction
• Magnetic order
• Magnetocaloric effect
• Skyrmions
• Topological order
• 2-dimensional systems
• Transition metal trichalcogenides
• First-principles calculations
• Monte Carlo methods
• Multiscale modeling