DNA Copy Number & Dilution Calculator

Presets are molecule-length shortcuts. Human 3.2 Gb is an approximate haploid reference, not a diploid cell count. E. coli K-12 MG1655 uses NC_000913.3; plasmids and inserts can differ from reference vectors. A measured plasmid molecule may contain multiple target sites; target copies equal molecule copies × verified target sites per molecule. This tool reports molecules, not genomic CNV or ddPCR Poisson-corrected partition counts.

660/330/340 are conventional coarse estimates, not exact sequence masses. Salt form, base composition, end groups and modifications affect MW; use a known full molecular weight for accurate oligo work. Alternative references use different approximations. Purity, degradation, measurement uncertainty, adsorption and pipetting losses are not modeled. Diluent must suit your assay; nuclease-free water is not automatically the best storage buffer. Display rounding does not change calculation precision. Plans have no overage; select adequate mixing/dead volume yourself.

Use the full length of the molecules whose mass you measured. For a plasmid, include backbone plus insert, not only the amplicon. For single-stranded DNA or RNA use bases / nucleotides, not base pairs.

A direct transfer below your selected minimum may be impractical. The planner inserts intermediate dilution steps, verifies material availability and labels the source tube for each transfer. Your minimum is an input, not a guarantee of pipette accuracy.

Only if the molecule contains one copy of the target. Verify target multiplicity, ploidy and sample composition before interpreting target-gene or cell equivalents.

Copies per reaction is an expected mean. Low-copy aliquots are stochastic, not guaranteed to contain that many molecules. In an ideal well-mixed Poisson model P(0) = exp(−λ). This is not a substitute for assay validation or ddPCR partition analysis. RNA templates require the appropriate reverse-transcription workflow for RT-qPCR.