Oligonucleotide Design & Analysis Tools
Free, scientifically accurate calculators for Tm, GC content, molecular weight, secondary structure prediction, and quality control. All calculations run locally in your browser—no data collection.
Tm Calculator
Melting temperature using SantaLucia method
GC Analyzer
GC content and distribution analysis
Structure Predictor
Hairpin and dimer detection
Batch Processing
Process 10,000+ sequences
Explore Tool Categories
Choose from our collection of specialized calculators and analysis tools, all designed with scientific accuracy in mind. Learn how to use them effectively in our use case guides or explore step-by-step tutorials.
Basic Calculators
Essential tools for daily oligonucleotide design
Sequence Analysis
Structure prediction and batch processing (10,000+ sequences)
Quality Control
Synthesis quality and pool uniformity analysis
Format Conversion
Convert between FASTA and CSV with validation
Why Use These Tools
Scientifically Accurate
Based on peer-reviewed methods (SantaLucia 1998, Breslauer 1986). All formulas and assumptions are transparent and documented. Learn more about our calculation methods in the User Guide and view complete citations in our Scientific References.
Privacy Focused
All calculations run in your browser. No sequences or results are transmitted to any server. No tracking, no analytics. Read our Privacy Policy for details, or check the FAQ for answers about data security.
100% Free
No registration required, no paywalls, no vendor bias. Built as a personal project for the research community. Try our Tm Calculator or explore all available tools to get started immediately.
Ready to Start Designing?
Browse all available tools or jump straight to the most popular calculator. No registration required, start calculating immediately. Need help? Check out our use case examples for step-by-step workflows, or visit the User Guide for detailed documentation.
Trusted by researchers worldwide