<p>Magnetic refrigeration is a promising and efficient cooling technology that uses the magnetocaloric effect (MCE), requiring particular materials with low heat capacity, low ordering temperature, and large magnetic moments for high performance. Here we report on Gd₂CrSbO₇, a mixed B-site pyrochlore oxide that exhibits a significant cryogenic MCE, driven by intricate 4<i>f</i>–3 <i>d</i> exchange interactions. Our combined experimental and theoretical investigation reveals that Gd₂CrSbO₇ crystallizes in a cubic pyrochlore structure (Fd3̅m) with ferrimagnetic (FiM) ordering, uniquely hosting a Griffiths-like phase and a Schottky anomaly arising from competing Cr–Cr short-range interactions and Gd crystal field effects. X-ray Raman spectroscopy confirms super-exchange interactions, while EXAFS analysis identifies enhanced Sb–O bond rigidity, influencing the material’s stability. Notably, Gd₂CrSbO₇ achieves a remarkable maximum magnetic entropy change of <InlineEquation ID="IEq1"> <EquationSource Format="TEX">\(-\Delta {S}_{M}^{\max}\)</EquationSource> <EquationSource Format="MATHML"><math> <mo>−</mo> <mi mathvariant="normal">Δ</mi> <msubsup> <mrow> <mi>S</mi> </mrow> <mrow> <mi>M</mi> </mrow> <mrow> <mi>max</mi> </mrow> </msubsup> </math></EquationSource> </InlineEquation> ≈ 21 J/kg K and refrigerant capacity of <i>RC</i> ≈ 430 J/kg (at 0−7 T), comparable to benchmark cryogenic refrigerants like Gd₃Ga₅O₁₂, but containing substantially low-priced elements. These findings position Gd₂CrSbO₇ as a promising platform for next-generation magnetic cooling, while shedding light on emergent magnetic and electronic phenomena in pyrochlore oxides.</p>