Sequence Length Counter

Count nucleotides in DNA/RNA or amino acids in protein sequences with detailed statistics and molecular weight calculation.

What is Sequence Length Counter?

Sequence length counter calculates the number of nucleotides in DNA/RNA or amino acids in proteins. Automatically detects sequence type and provides molecular weight estimation.

How to Count Sequence Length

Quick guide to get results:

  1. Paste DNA, RNA, or protein sequences
  2. Tool auto-detects sequence type
  3. View length, MW, and statistics

When to Use

This tool is useful when you need to:

  • Checking primer or oligo lengths
  • Validating sequence data quality
  • Comparing multiple sequence lengths
  • Calculating molecular weights

Example Input

Sample input:

>Seq1 ATCGATCGATCG >Seq2 GGCCGGCC

Try with your own sequence or use the Example button.

Example Output

Expected output format:

Seq1: 12 nucleotides Seq2: 8 nucleotides Total: 20 nucleotides

Results can be copied or downloaded.

FAQ

Q: Does this tool handle FASTA format?
A: Yes, both single and multiple sequences.

Q: How does it detect sequence type?
A: Checks for U (RNA), EFILPQZ (protein), or defaults to DNA for ATCGN only.