How to Use the DNA Ligation Calculator
Calculate insert DNA mass for recombinant plasmid cloning:
Enter Vector Mass
Input linearized plasmid vector mass in nanograms (typically 20-100 ng).
Enter Vector Length
Provide vector backbone size in base pairs (e.g. 4000 bp).
Enter Insert Length
Provide insert gene fragment size in base pairs (e.g. 1000 bp).
Select Molar Ratio
Choose 3:1 or 5:1 molar ratio and get exact insert mass required.
Key Features & Recombinant DNA Math
Molar Ratio Stoichiometry
Ensures equal molar presence of sticky ends for optimal T4 DNA ligase efficiency.
Sticky & Blunt End Support
Supports custom 1:1 up to 10:1 ratios for restriction enzyme digestion cloning.
100% Private Client Compute
Runs in browser memory with zero tracking or server logs.
Cloning Guide: Optimizing DNA Ligation Reactions
In recombinant DNA technology, T4 DNA ligase catalyzes the formation of phosphodiester bonds between 5'-phosphate and 3'-hydroxyl termini. Calculating molar ratios prevents vector self-ligation (re-circularization) and maximizes transformation efficiency in E. coli.
Frequently Asked Questions
?How is insert mass calculated for ligation?
Insert Mass (ng) = (Vector Mass (ng) × Insert Length (bp) / Vector Length (bp)) × Molar Ratio.