Sanger chromatogram viewer
Open an Applied Biosystems .ab1 file to view the four dye traces, base calls, and quality bars. Optionally paste a reference DNA sequence to highlight mismatches — useful for cloning QC and mutation checks after Sanger sequencing.
Parsing runs entirely in your browser; traces are not uploaded. Pair with sequence aligner, CloneIT2, or DNA reverse & complement when checking inserts.
Drop or choose an .ab1 file to view the chromatogram.
Called bases
Quality values
How this tool works
AB1 files store dye intensity traces (DATA), base calls (PBAS), peak locations (PLOC), and optional qualities (PCON). This viewer reads those ABIF tags locally and draws A/C/G/T traces with called bases above the peaks.
Reference comparison
Comparison uses a sliding ungapped window to place the called read on the reference, then lists base mismatches. It does not perform full gapped alignment — for indel-heavy reads use the sequence aligner on the exported FASTA.
Privacy
Files stay in your browser. Nothing is sent to The Bond Lab servers.