Reverse Complement Calculator

Compute reverse, complement, or reverse-complement for DNA/RNA sequences with FASTA support.

Reverse, Complement, and Reverse Complement Tool

DNA/RNA Sequence Manipulation Guide

Our tool offers three essential functions for bioinformatics sequence analysis: Reverse, Complement, and Reverse Complement. These are fundamental operations for tasks like primer design, sequence alignment, and ORF finding.

  • Reverse: This function simply reverses the order of your input DNA or RNA sequence. It is useful for preparing sequences for alignment or comparison.
  • Complement: This generates the corresponding complementary strand of your DNA or RNA sequence. It replaces each base with its complement (A with T/U, G with C, and vice versa).
  • Reverse Complement: This is a two-step process that first reverses the sequence and then generates the complement. The reverse complement is crucial for finding features on the opposite strand of a DNA molecule.

Important Considerations:

  • Supported Formats: The tool accepts both raw DNA/RNA sequences and FASTA-formatted sequences. If a FASTA header is detected, it will be preserved in the output.
  • Large Datasets: This tool supports converting hundreds or thousands of sequences. You can download the result as a file after conversion.
  • Ambiguity Codes: We support IUPAC ambiguity codes. Two-nucleotide codes are converted as R↔Y and K↔M, while S and W remain unchanged. Three-nucleotide codes are handled as B↔V and D↔H.
  • Case Preservation: The case of the input sequence is preserved in the output, allowing you to mark regions of interest.
  • Client-Side Processing: All calculations are performed directly in your browser. Your data remains private and is never sent to our servers.

Nucleotide Ambiguity Codes

Ambiguity codes are used in bioinformatics to represent positions in a DNA or RNA sequence where the exact nucleotide may not be known. Our tool supports the full range of IUPAC ambiguity codes, ensuring accurate conversions for complex sequences. Below is a detailed table of these codes and their complements, as handled by our tool.

CodeNucleotidesComplement
AAT
GGC
CCG
TTA
UUA
RA or G (purine)Y
YC or T (pyrimidine)R
SC or G (strong)S
WA or T (weak)W
KG or T (keto)M
MA or C (amino)K
BC, G, or T (not A)V
VA, C, or G (not T)B
DA, G, or T (not C)H
HA, C, or T (not G)D
-gapunchanged
any otherany or unknownunchanged

How to Use

  1. Paste or type your DNA/RNA sequence (raw text or FASTA).
  2. Select the operation you need: reverse, complement, or reverse complement.
  3. Copy or export the result for downstream analysis (primers, strand checks, annotations).

FAQ

What is the reverse complement used for?

It is commonly used to analyze features on the opposite strand, design primers, and work with strand-specific annotations.

Does it support ambiguity codes?

Yes. IUPAC ambiguity codes are supported (e.g., R↔Y, K↔M, B↔V, D↔H), and case is preserved.