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DNA Input Calculator

Calculate DNA Volume Needed for PCR Reactions

Calculate DNA Volume

From Qubit or NanoDrop measurement

Target: 10 ng DNA per reaction

DNA Volume = 10 ng ÷ Concentration
Water Volume = 10 μL - DNA Volume

Calculated Volumes

DNA Volume
-
μL
Water Volume
-
μL
Total Volume
10.0
μL

Good to go!

Add - μL of DNA + - μL of water to each PCR tube

Warning: Very Low Concentration!

Consider concentrating your DNA sample using vacuum centrifugation or ethanol precipitation.

Instructions:

1. Add calculated DNA volume to each PCR tube

2. Add calculated water volume to reach 10 μL total

3. Then add 15 μL of PCR master mix (from Master Mix Calculator)

4. Final reaction volume: 25 μL

Common Concentration Examples

Concentration DNA Volume Water Volume Total
0.5 ng/μL 20.0 μL 0.0 μL 20.0 μL
1.0 ng/μL 10.0 μL 0.0 μL 10.0 μL
2.0 ng/μL 5.0 μL 5.0 μL 10.0 μL
5.0 ng/μL 2.0 μL 8.0 μL 10.0 μL
10.0 ng/μL 1.0 μL 9.0 μL 10.0 μL
20.0 ng/μL 0.5 μL 9.5 μL 10.0 μL
50.0 ng/μL 0.2 μL 9.8 μL 10.0 μL

Concentration Range Guide

Visual guide for typical DNA concentrations

Too Low
< 0.5 ng/μL

Need >10 μL DNA

Concentrate sample

Workable
0.5 - 2 ng/μL

5-10 μL DNA needed

No water needed

Ideal
2 - 10 ng/μL

1-5 μL DNA

Easy to pipette

High
> 10 ng/μL

<1 μL DNA

Precise pipetting