Abstract: Published data of NMR ¹H spectra of linear alkanes X-(CH2)_n-Y (I), (X = H; Y - 38 different substituents, including H and CH₃; n = 1 ÷ 36) were considered. The universal way to estimate the chemical shifts of the methylene groups pronons (δ^H_CH2 = δ^H_i, i = 1 ÷ 36) in I was proposed. It is based on the concept that considers changes in the values δ^H_i of each methylene pronons in I (called as increments Δδ^H_i) as a result of conversion to I of a hypothetical alkane with an infinitely long chain -(CH₂)_k-(CH₂)_n-(CH₂)_l- (II) by replacing infinitely long fragments -(CH₂)_k- and -(CH₂)_l- of it with the substituents X and Y. The values δ^H_i of each methylene group in II are assumed the same and equal to that of the medium methylene groups in long-chain alkanes (1.27 ppm). Equal to or greater than 0.02 ppm values of Δδ^H_i increments are observed in only r closest to the X and s closest to Y methylene pronons in the H-(CH₂)_r-(CH₂)_t-(CH₂)_s-Y (I). Parameter r = 3 is constant as a value δ^H_t = 1.27 ppm, but the parameter s = 2 ÷ 5 is variable, depending on the nature of the substituent Y. All Δδ^H_i increments for each substituent Y are calculated using the formula: Δδ^H_i = δ^H_i – 1.27 ppm, and tabulated. Relationship between the parameters r, s and t determines the length of alkyl chain. All compounds I conditionally divided into three groups: long-chain (n> r + s + t), medium-chain (n