<p>In the present study, lead-free high entropy Sn₂₅Cu₁₅Al₂₀Mg₂₀Zn₂₀ solder alloy was produced. High entropy solder alloys were prepared by pressing-sintering (powder metallurgy). High entropy alloys are novel engineering materials with 5–13 principle elements in near-equal contents and tend to form a solid solution instead of brittle intermetallics. Formation of intermetallics is the main drawback in the traditional solder alloys. Thick brittle intermetallic compounds film could degrade the mechanical properties of solders. Elimination of brittle intermetallic compounds by formation of solid solution could enhance the strength. High entropy alloys forms solid solution instead of brittle intermetallics for their high entropy effect and sluggish diffusion effect. Sn–Pb and Sn–Pb–Ag–Cu are most common solder alloys due to their strength, wettability, low melting temperature, corrosion resistance, electrical conductivity, and low cost. Pb has toxic effect, while. Ag has brittle intermetallic formation effect. Sn, Mg, Ti, Cu, Al, and Zn added due to their melting temperature, electrical conductivity, density, corrosion resistance, mechanical properties, cost values, which are suitable for solder applications. Also, Sn, Cu, Al, Mg, Ti, Zn elements were added due to their entropy of mixing, enthalpy of mixing, atomic size, valance electron concentration values, which are suitable for high entropy alloy formation. High entropy solder alloys manufactured by powder metallurgy. Initially, metal powders were mechanical alloyed for 40&#xa0;h with ZrO₂ balls having 6&#xa0;mm diameter. Secondly, the alloy particles were pressed. Finally, the green samples sintered at 180&#xa0;°C for 60&#xa0;min. Lastly, first principles-based computational materials science study was carried out in order to obtain elastic, mechanical and physical properties of the alloys. Sn₂₅Cu₁₅Al₂₀Mg₂₀Zn₂₀ (alloy-7) was the most suitable alloy suitable ΔH_mix, high ΔS_mix and low melting temperature.</p>