CodonBench: codon optimization for expression

CodonBench redesigns a gene's codons to suit your expression host while keeping the protein identical, and reports the codon adaptation index, GC content, and rare codons before and after.

Open CodonBenchAll tools

Free, no sign-up, and installable on your phone. Runs in your browser at codons.gataca.com.

CodonBench showing results for the built-in example
CodonBench with its built-in example loaded.

What you can do with CodonBench

  • Prepare a gene for synthesis and expression in E. coli
  • Move a human or viral gene into yeast or mammalian cells
  • Remove restriction sites you need for cloning
  • Find rare codons that may slow translation

How to use it

  1. Paste a protein sequence or a coding DNA sequence.
  2. Choose the expression host and the optimization method.
  3. List any restriction sites to keep out of the design.
  4. Copy the verified, optimized DNA and compare CAI and GC with the original.

Features

  • Codon usage tables for E. coli, S. cerevisiae, and human
  • Most-frequent and usage-matched optimization
  • Codon Adaptation Index (CAI) before and after
  • Rare codon highlighting
  • Restriction site removal
  • Automatic check that the protein is unchanged
  • Save results as reports, spreadsheets, or sequence files
  • Install it on your phone or computer; works offline

Frequently asked questions

Which method should I choose?

Match host usage is usually the better default because it avoids repetitive sequence while skipping rare codons. Most frequent codon maximizes CAI when that matters more.

Why does changing the seed give a different sequence?

Usage-matched optimization chooses among good codons at random in proportion to host usage. The seed makes each design reproducible.

Can I add another organism?

Not yet. Contact us if you need a specific host; we can add its codon usage table.

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