In-Fusion® Molar Ratio Calculator

The tool below will help you to calculate optimal amounts of vector and insert for the In-Fusion® Cloning reaction. All you need to do is enter your vector and insert sizes in base pairs.

Insert/Vector Ratio: (recommended 2)
Vector size (bp):
Insert size (bp):
Amount of Vector (ng):
Amount of Insert (ng):


1. We recommend using at least 50 ng of a DNA insert in your cloning reactions.

2. The Molar Ratio Calculator is optimized for use with standard sized vectors and inserts. Typically, In-Fusion reactions work well with 100 ng of a 4-5 kb linearized vector plus 50 ng of a 1 kb PCR product. If your vector and PCR product differ greatly in size (e.g., you are using a 12 kb vector and 60 bp insert), the Molar Ratio Calculator may recommend using less than 50 ng of insert. If this is the case, you will need to adjust the amount of DNA to ensure that a minimum of 50 ng of insert is used. Please refer to In-Fusion User Manual for more detailed recommendations.