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.
Choose from our collection of specialized calculators and analysis tools, all designed with scientific accuracy in mind. Learn how in our use case guides or explore step-by-step tutorials.
Essential tools for daily oligonucleotide design
Structure prediction and batch processing (10,000+ sequences)
Synthesis quality and pool uniformity analysis
Convert between FASTA and CSV with validation
Based on peer-reviewed methods (SantaLucia 1998, Breslauer 1986). All formulas and assumptions are transparent and documented.
All calculations run in your browser. No sequences or results are transmitted to any server. No tracking, no analytics.
No registration required, no paywalls, no vendor bias. Built as a personal project for the research community.
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