Markers and Ladders

DNA Markers & Ladders

NEB offers a variety of DNA Ladders with sizes ranging from 25 bp to 48.5 kb for use in agarose gel electrophoresis. NEB also offers a wide range of double-stranded DNA molecular weight markers for conventional agarose gel electrophoresis. These standards have a size range of approximately 10 bp to 23,000 base pairs.

The typical pattern generated by each of our markers and ladders is shown below.  Fragment sizes are indicated alongside of the image.  Relative mass values are also shown, when appropriate.

Convenient Formats

Our 2-log, 1 kb and 100 bp DNA Ladders are offered in four formats.  Choose from the conventional ladder, the Quick-Load® version (using either non-fluorescing purple dye or bromophenol blue) or TriDye®™ (containing three dyes to facilitate the monitoring of migration).  Quick-Load Purple versions also include a vial of dye, free of charge.

UV Shadow Comparison

The new Gel Loading Dye, Purple (6X) (Lane 1) included in the Quick-Load Purple 1 kb DNA Ladder does not cast a UV shadow over the underlying bands, unlike the Gel Loading Dye, Blue (6X) (Lane 2).

Featured Products


  • DNA Ladders are supplied with 1 vial of Gel Loading Dye
  • Suitable for analysis of a wide range of DNAs
  • Uniform band intensities and convenient band spacing
  • Easy-to-identify reference bands
  • DNA Ladders can be used for sample quantitation

TriDye and Quick-Load Formats

  • TriDye™ Ladders: 1 kb, 100 bp and 2-Log DNA Ladders are available in ready-to-load format containing xylene cyanol FF, bromophenol blue and orange G.
  • Quick-Load® Ladders: 1 kb, 1 kb extend, 50 bp, 100 bp, 2-Log, Low Molecular Weight DNA Ladders and PCR marker are available in ready-to-load format containing either non-fluorescing purple dye or bromophenol blue as a tracking dye.

Comparison of NEB to Other Commercially Available DNA Ladders

Comparison of the NEB 1 kb (left) and 100 bp (right) DNA Ladders to other commercially available DNA Ladders. Note: The 500 bp DNA Ladder from Roche is used in the 1 kb DNA Ladder comparison.

DNA Markers & Ladders Selection Chart