Built for African molecular biology labs

Design PCR primers with confidence — in your browser.

PrimerLab is a free, real-time co-pilot for students and researchers in Molecular Biology and the Biological Sciences. Paste your DNA template — get instant melting temperatures, GC content, hairpin and dimer warnings, and a clear binding map. No installs. No expensive licences.

Create your free account Try the lab

Free for students University-friendly SantaLucia 1998 thermodynamics

Live binding mapDemo

5'  ATGGCCATTGTAATGGGCC...AGCTAGCATGCATCGATCG  3'
    ───────────              ──────────
    ↑ forward primer         reverse primer ↑

   Tm (F): 60.2°C    Tm (R): 60.6°C    ΔTm: 0.4°C
   GC (F): 55.0%     GC (R): 52.0%
   Amplicon: 184 bp
   Hairpin: clear    Self-dimer: clear   Heterodimer: clear

Tm match

0.4°C

Amplicon

184 bp

Structures

Clear

Everything you need for a successful PCR

Every keystroke is analysed in real time, so you learn the rules of good primer design while you work.

Real-time melting temperature

Accurate Tm using SantaLucia (1998) nearest-neighbor thermodynamics with salt correction, updated on every keystroke.

GC content & homopolymers

Instant GC% with optimal-range guidance, plus warnings for any single base repeating more than four times.

Secondary-structure scan

Catches hairpins, self-dimers, and heterodimers before you order primers — saving time and reagents.

Visual binding map

See exactly where forward and reverse primers land on the template, plus the predicted amplicon size.

Auto-design assistant

Paste a template and PrimerLab proposes a balanced primer pair you can fine-tune from there.

Friendly for learners

Clear colour-coded indicators teach you what 'good' looks like — perfect for coursework and final-year projects.

Built with African universities in mind

From a final-year project at the University of Lagos to a malaria genomics lab in Nairobi — PrimerLab works on a phone, on a slow connection, and without a paid licence. Whether you study Molecular Biology, Biochemistry, Microbiology, Genetics, or any of the Biological Sciences, you can get to a clean primer pair in minutes.

Undergraduate Molecular Biology & Biochemistry students
Postgraduate researchers in Genetics & Microbiology
Final-year project students designing diagnostic assays
Lecturers preparing PCR practicals and tutorials
Public-health and agricultural research labs
Bioinformatics & biotechnology clubs on campus

Three steps to a primer pair

Step 1

Paste your DNA template

Drop in any A/T/G/C sequence — non-DNA characters are cleaned automatically.

Step 2

Review live metrics

Watch Tm, GC, structures and binding update on every keystroke. Adjust until everything is green.

Step 3

Order with confidence

Copy your validated primer pair into your synthesis order — no guesswork left behind.

Start designing better primers today

Create a free account to save your primer designs and pick up where you left off — from any device, any campus.