SeqBench

A Sequence Workbench for Cloning, CRISPR & Primer Design

From PCR primers and clone assembly to CRISPR guides and plasmid maps.
All in one browser workbench.

The SeqBench workbench

SeqStudio — a real, editable sequence & plasmid editor

Type or paste DNA and edit it directly — every annotated feature remaps live as you insert, delete, or replace bases, even across a circular plasmid's origin. Restriction digests, a virtual gel, auto-annotation, undo/redo, multi-document tabs, and GenBank / SnapGene .dna import & export — all running locally in your browser.

  • Live restriction digest & virtual gel
  • Auto-annotation & feature editing
  • GenBank / SnapGene .dna import & export

Workflows

Sequence manipulation

Translation & ORFs

Analysis & design

GC Content

Calculate GC%, AT% and per-base composition for DNA or RNA.

Primer Tm

Estimate primer Tm, GC% and molecular weight from a sequence.

Oligo Analyzer

Nearest-neighbor Tm, ΔG, hairpins and primer dimers for any oligo or primer pair.

Oligo Cofold

Fold one oligo, or two together, with ViennaRNA's loop model at your annealing temperature — hairpin, self-dimer and heterodimer ΔG, plus the interaction ΔG.

Primer Designer

Design ranked PCR primer pairs from a template, with Tm, GC and dimer checks.

Mutagenesis Primers

Design SDM primers from a nucleotide or amino-acid change, QuikChange or Q5 style.

Restriction Sites

Find recognition and cut sites for common restriction enzymes.

Double Digest Buffer

Pick two restriction enzymes and get the single buffer that runs both, each enzyme's activity in every buffer, and a straight answer on when to digest sequentially instead.

FASTA/FASTQ Stats

Summarise and validate FASTA or FASTQ: counts, N50, GC, quality.

DNA Molarity / ng↔pmol

Convert between mass, moles, molarity and copy number for DNA/RNA.

Ligation Calculator

Turn a 3:1 insert-to-vector molar ratio into the microlitres you actually pipette, for one insert or a whole multi-fragment assembly.

In-silico PCR

Enter a template and two primers to predict the PCR product, its size and position.

CRISPR gRNA Designer

Scan a sequence for SpCas9, SaCas9 or Cas12a guide candidates with PAMs and scoring.

CRISPR Off-Target Check

Screen a guide's protospacer against curated lab reference genomes — SpCas9 hits ranked by CFD, not by mismatch count.

Gene ID Mapper

Convert gene symbols, Ensembl, Entrez GeneID, RefSeq and UniProt accessions in batch, and find cross-species orthologs.

Prime Editing Studio

Design SpCas9 pegRNAs for any substitution, insertion, deletion or small replacement — spacer, PBS sweep, RTT and 3' extension, PE3 nicking guides, plus twinPE dual-pegRNA design for large edits.

Prime Editing Efficiency

Score every PBS/RTT combination for one prime edit with PRIDICT2.0 and rank the pegRNAs — HEK293 and K562 scores, library percentiles, the full pegRNA, and Golden Gate cloning oligos.

siRNA / shRNA / ASO Designer

Design knockdown reagents against an mRNA — Reynolds/Ui-Tei-scored siRNAs with ready shRNA cassettes, or 5-10-5 ASO gapmers screened for known liabilities.

KASP / ARMS Primer Designer

Design KASP/ARMS SNP-genotyping primers — two allele-specific forward primers with FAM/HEX tails and an engineered ARMS secondary mismatch, plus a common reverse primer.

Gel Troubleshooter

Diagnose gel problems (no bands, smearing, wrong size, primer-dimer, degradation) with a fully deterministic symptom guide that links to the right SeqBench tools.

Base Editing Designer

Find CBE (C→T) or ABE (A→G) base-editing gRNAs that place your target base in the editor's activity window, with bystander flags and amino-acid consequences.

RNA Structure (MFE)

Fold an RNA to its minimum-free-energy secondary structure — dot-bracket, MFE, base-pair list and an exportable arc diagram, without installing ViennaRNA.

Gene Explorer

Search a gene and get its exon/CDS structure, a druggability/disease/drug/trial/paper dossier, and a GTEx + Human Protein Atlas expression fingerprint — all in one page.

Functional Enrichment

Test a gene list for enriched GO terms and Reactome pathways with hypergeometric p-values and BH-FDR correction.

PCR Plate Planner

Lay out PCR reactions on a 96-well plate and export a runnable Opentrons protocol or Echo picklist.

RBS Designer

Predict the translation initiation rate at every start codon, and design a 5' UTR to hit a target expression level, with OSTIR and ViennaRNA.

Diagnostic Digest Planner

Find the restriction digest that tells your intended construct apart from the empty vector, a flipped insert or a mis-assembly — with the bands you would actually be able to read.

Golden Gate Fidelity

Score your 4-base Golden Gate / MoClo overhangs against real published T4-ligase ligation counts: the weakest junction, every risky pair, and how your set compares with a published one.

Plasmid Stability Checker

Locate the exact direct repeats that let a construct recombine away the DNA between them, and build the shortened molecule you would actually recover.

Band Traceback

Work backwards from the size you measured: which pairs of priming sites on your template could make a product that big, and can their 3' ends actually extend?

CRISPR Editing Efficiency

Drop in an unedited control trace and your edited pool's trace and get the indel spectrum, the unedited fraction, and the R² that says whether the decomposition means anything.

Multiplex PCR Panel Design

Choose one primer pair per target so no two cross-dimerise, every amplicon is separable on the gel, and one annealing temperature serves the whole panel.

Vector library

308 publicly deposited vectors with their full GenBank feature tables, and 617 parts harvested from them.

Cloning Troubleshooter

No colonies, every clone empty vector, or no PCR band: get the causes your design and your control plates actually implicate, and the cheapest experiment that separates the top two.

Base Editing Quantification

Load an unedited control trace and your edited pool's trace and get per-position C→T or A→G percentages, their z-scores against your own run's background, and the detection limit those numbers sit on.

HDR Donor Designer

Build a knock-in donor with homology arms around a Cas9 cut site, fold in a PAM-blocking mutation, and get primers that genotype the edit.

Knock-in Quantification

Put the intended allele itself in the basis: measure what fraction of the pool carries your knock-in, what fraction is still wild type, and what fraction is NHEJ byproduct — from one control trace and one edited trace.

Oligo Pool Screen

Screen a whole oligo pool for cross-dimers between members, each oligo's own hairpin and self-dimer, duplicates and Tm spread.

Proteins & peptides

Alignment & visualization

MSA Viewer

Align several DNA or protein sequences and view a colored alignment with a consensus.

Virtual Gel

Predict restriction fragments and see the simulated agarose gel with a ladder.

Variant Comparator

Align a query to a reference and list substitutions, insertions and deletions with effects.

Pairwise Alignment

Align two sequences with Needleman-Wunsch or Smith-Waterman.

Plasmid Viewer

Render a circular or linear map with restriction sites.

GenBank Viewer

Paste a GenBank record and see an annotated circular or linear map with a feature table.

Sanger Trace Viewer

View an .ab1 / .abi Sanger chromatogram, read the base calls and export the trace.

Sanger vs Reference

Align a Sanger read to a reference and get a pass / needs-review verification report.

Sequencing Read-Back Verification

Align many NGS/Nanopore/Sanger reads to a reference with minimap2, call multi-read consensus variants, and build a corrected consensus sequence.

Verify Construct

Paste what you got back and the PCR you say made the insert. It re-derives the insert, finds it in either orientation, and gives you the exact mismatch positions.

Plasmid Annotator

Auto-detect promoters, tags, origins and resistance markers in a plasmid, then run a deep scan against pLannotate's full feature databases.

Identify Plasmid

Paste an unlabelled plasmid and get its closest classic backbone, whether it looks like a chimera of two, and every stretch that neither a known backbone nor a known feature accounts for.

Volcano Plot

Plot log2 fold-change vs. significance from a DESeq2/edgeR/limma table, with draggable thresholds.

Clustered Expression Heatmap

Cluster and visualize a gene x sample expression matrix with row/column dendrograms.

HGVS Converter

Convert an HGVS c. variant to genomic (g.) coordinates and predict its protein (p.) effect, via a real, live Ensembl exon map.

Variant Annotator

Look up a variant by rsID, chrom:pos:ref:alt, or HGVS and get its ClinVar significance, gnomAD allele frequencies, and CADD/SIFT/PolyPhen2/REVEL scores in one card.

SeqStudio

Type or paste a sequence and edit it directly — every feature remaps live as you insert, delete, or replace bases, with undo/redo and GenBank import/export.

FASTQ QC Report

Per-base quality, GC and length distributions, duplication levels, overrepresented sequences and adapter content, each with a warn/fail verdict.

Sanger Clone Screening

Drop a plate of Sanger reads against one construct and get one row per clone: which colonies to grow up, and why.

Plasmid Identifier

Screen an unknown plasmid against 30 curated common backbones and rank the candidates by identity and coverage.

New to a technique? Read the step-by-step guides, look up a reference table such as the codon table, or ask SeqBench-GPT in plain language.