DNA is double‑stranded and antiparallel. The reverse complement of a sequence is the complementary strand read in the 5'→3' direction. This tool supports IUPAC ambiguous bases (R, Y, N, etc.) and can switch between DNA and RNA modes. All processing is done locally — your sequence never leaves your browser.
It is the sequence of the opposite strand, reversed (to maintain 5'→3' orientation) and complemented (A↔T, C↔G). For RNA, U replaces T.
IUPAC codes represent multiple possible bases (e.g., R = A or G, Y = C or T, N = any base). This tool correctly complements all standard IUPAC codes.
GC% = (number of G + C bases) / (total bases) × 100%. Non‑standard bases (IUPAC codes) are ignored in the calculation.
No. All processing is done locally in your browser using JavaScript. Your data never leaves your device, ensuring complete privacy.
Yes, enable "RNA Mode" to automatically convert T to U (or U to T) and use the appropriate complement table (A↔U, C↔G).