The invention relates to a nucleic acid marker ladder which is a restriction endonuclease digest, wherein a nucleic acid restriction endonuclease digest is a collection of nucleic acid fragments resulting from complete digestion of one or more nucleic acids by one or more restriction endonucleases; the restriction endonuclease digest contains at least 3 fragments; and the size of the fragments in base pairs is a multiple of an integer, wherein the integer is 10 or more.