Scale a PCR or qPCR master mix
This master mix calculator converts a per-reaction recipe into the total volume of each reagent needed for PCR, qPCR, enzyme reactions, cloning assemblies, or other repeated lab setups. Enter each component once, choose the number of reactions, and add an overage percentage to compensate for liquid retained in pipette tips and tubes.
For each shared reagent, the calculator uses total volume = volume per reaction × reaction count × (1 + overage/100). A 10% overage for 12 reactions therefore prepares the equivalent of 13.2 reactions. Components marked as per-reaction only, such as individual DNA templates, stay out of the pooled master mix.
Practical master-mix workflow
- Copy the per-reaction volumes from the validated assay protocol, including water.
- Count experimental samples and required controls, then choose an appropriate overage.
- Prepare the shared mix, dispense the calculated amount into each tube or well, and add unique templates separately.
The PCR preset is an editable starting layout, not a replacement for the polymerase or assay manufacturer's protocol. Check reagent concentrations, reaction volume, control count, and template handling before pipetting.
Frequently used components can be selected from the reagent inventory tracker, which keeps lot, concentration, location, and expiry details together.
PCR master mix FAQ
How much extra master mix should I prepare?
Many workflows use 5–10% extra, but the right overage depends on reaction count, liquid volume, pipette, and protocol. Follow the validated method used by your lab.
Should DNA template be included in the master mix?
Only when the same template belongs in every reaction. Unique samples and controls are normally added to individual tubes or wells, so mark them as per-reaction-only components.
Does this work for qPCR and non-PCR reactions?
Yes. The calculator scales any volume-based per-reaction recipe, including qPCR mixes, restriction digests, ligations, and enzyme assays.