Everything you need
at the bench.
I had the same handful of websites bookmarked for things like nucleic acid mass-to-molarity conversion and bradford assays for protein concentration. Then when I was discussing calculating tRNA concentrations with my PhD student I had to share one of these old sites, and considering I had already made my FeeDings! RSS app I asked myself why I had not made a science one. One that worked offline, had no ads, and had everything a molecular biologist, biochemist, or biology student actually needs in one place. A molecular biology calculator, a biochemistry calculator, a lab protocol app, a 414-term science glossary with molecular structures, educational content that builds from first principles, and lab safety guides.
Dr Jason Woodgate, postdoctoral research associate, Newcastle University. Join the conversation.
App in Action
Screenshots and video walkthrough. See BenchCalc running before you download.
55 Tools Across 9 Categories
55 tools across 9 categories. Dilution calculators, Tm prediction, protein concentration, buffer preparation, and more. Offline, no ads.
Nucleic Acids
DNA molarity calculator for mass-to-moles conversion, A260 DNA concentration calculator from spectrophotometer readings, primer Tm calculator with nearest-neighbour melting temperature prediction, primer pair comparison, and dimer checking. Primer resuspension calculator from lyophilised tubes with working stock dilution. Agarose gel calculator for pouring with TAE/TBE buffer selection, EtBr/SYBR Safe stain volumes, and a percentage-to-resolution size guide.
Protein Tools
Protein molecular weight calculator from amino acid sequence, Bradford assay calculator and BCA assay calculator with standard curve or quick estimate mode for protein concentration. Beer-Lambert A280 absorbance protein concentration calculator. Isoelectric point calculator for peptides with Henderson-Hasselbalch, per-moiety charges, and a charge-vs-pH curve. Enzyme unit converter between U/mg, nmol/min/mg, umol/min/mg, and kcat. PAGE gel calculator for SDS-PAGE, native, and denaturing gels with resolving and stacking recipes, cassette size presets, and urea calculations.
Dilutions & Solutions
C1V1 C2V2 dilution calculator, serial dilution planner with step-by-step pipetting volumes, molarity calculator for solution preparation, percent solution calculator for w/v, v/v, and w/w, normality calculator with equivalence factors and N1V1=N2V2, and a resuspension calculator. These are the tools I reach for every single day. You probably do too.
Buffers & Reagents
Buffer calculator for preparation with common buffer systems, Henderson-Hasselbalch equation solver for target pH, and stock solution preparation from solid reagents. The multi-solute buffer builder lets you select reagents from the built-in reagent database, set target concentrations, and get a complete recipe with mass or volume for each component. No more guessing at buffer recipes.
Cell & Lab Tools
Cell culture calculator with haemocytometer cell counting, cell seeding density planner for plates and flasks, centrifuge RCF/RPM converter with rotor radius input, doubling time calculator from growth curve data, radioactive decay calculator with preset isotopes (including P-32, S-35, I-125), reference date or elapsed time input, activity unit conversion, and a decay curve. Lab timer with multiple simultaneous countdowns and 28 presets across 5 categories.
PCR & Cloning
PCR master mix calculator with enzyme presets, template DNA concentration helper, and automatic 10% overage. Restriction digest calculator where you select up to 3 enzymes from the built-in database with automatic buffer compatibility checking, methylation and star activity warnings. Ligation calculator with insert:vector molar ratios, enzyme presets (T4 cohesive, T4 blunt, Quick Ligase, Instant Sticky-End), and full reaction volume breakdown. General reaction mix with C1V1=C2V2 scaling.
Sequence Analysis
Sequence translator with DNA, RNA, and protein conversion, auto-detection, reverse complement, six reading frames with ORF highlighting, and feature annotation. Annotates start/stop codons, Shine-Dalgarno sequences, promoters, Kozak sequences, and poly-A signals with a prokaryotic/eukaryotic toggle and sequence map overview. Bioinformatics in your pocket, as it should be.
Utilities
Unit converter with full SI magnitude ladder (femto to peta) across 7 categories. Quick calculator with expression history, memory, and shortcut chips to jump to other tools. Lab timer with multiple simultaneous countdown timers and 28 presets across 5 categories. Timers keep running while you use other tools, because experiments do not pause while you calculate.
More Than Calculators
There is no point where chemistry stops and biology begins. It is all the same probability dance at different scales, and understanding that changes how you approach every experiment. A glossary, educational reference, lab safety guide, and practical tips, written by a working scientist.
Glossary - 414 Terms
A biology glossary and science glossary covering 10 categories: molecular biology, DNA/RNA, protein, organic chemistry, microbiology, practical techniques, systems biology, structural biology, statistics for biology, and general scientific vocabulary. Each entry includes molecular structure rendering for chemical compounds, with seamless navigation to related educational content, safety guides, and lab tips throughout the app.
Learn & Understand - 91 Entries
Educational content across 11 scientific disciplines, from the foundations of science through physical chemistry and biochemistry to experimental design and scientific writing. Written to build from first principles upward, grounding everything in underlying chemistry and physics before scaling to biology. The scientific writing guide covers papers, theses, grants, posters, presentations, and reviewer responses.
Lab Safety - 20 Guides
Chemical safety and lab safety guides across 5 sections: acids and bases, organic solvents, biological and mutagens, toxic reagents, and physical hazards. Each entry has structured handling instructions, spill response procedures, and first aid, with LD50 toxicity data where relevant. Having this information accessible at the bench, offline, matters.
Lab Tips - 45 Tips
Practical technique tips across 6 sections: pipetting, gel electrophoresis, cell culture, protein work, DNA and RNA work, and equipment. These are the things you learn from years at the bench that nobody writes down in a protocol, but that make the difference between an experiment that works and one that wastes a week.
13 Lab Protocols
Interactive step-by-step guides for when you need a full walkthrough or just a sanity check on something you have not done in a while. Checklist and focus modes, duration badges, volume chips, warnings, and tips. Progress saved per protocol. Cross-linked to troubleshooting wizards.
Molecular Biology
Miniprep (alkaline lysis plasmid purification), ethanol precipitation of nucleic acids, gel extraction and purification, and PCR product cleanup. The protocols you run weekly, written the way they actually work.
Cloning & Transformation
Cloning design (in silico planning), cloning practical (bench workflow), restriction enzyme digest setup, DNA ligation protocol, and heat shock transformation of competent E. coli. Step-by-step from design to colony, with the timings and temperatures that matter.
Protein & Culture
E. coli growth and harvest for protein expression, affinity column purification (His-tag / GST-tag), column maintenance and regeneration, and inclusion body purification with urea/guanidine solubilisation routes and refolding screen guide.
7 Troubleshooting Wizards
When experiments fail, most troubleshooting advice is a flat list that does not help you narrow down the problem. BenchCalc includes interactive diagnostic wizards that walk you through what went wrong and what to do next.
Cloning
No colonies, wrong insert, multiple bands, religation background, and transformation failures. Step-by-step diagnosis from plate to gel.
PCR
No product, non-specific bands, smears, primer dimers, and low yield. Covers Tm mismatches, template quality, and cycling conditions.
Restriction Digest
Incomplete digestion, star activity, unexpected fragments, and buffer incompatibility. Includes double digest troubleshooting.
Agarose Gel
Smeared bands, no migration, fuzzy bands, and unexpected sizes. Real gel images with toggleable comparisons.
Protein Expression
No expression, insoluble protein, low yield, and degradation. Covers IPTG induction, temperature, and host strain selection.
Protein Purification
No binding, low purity, elution problems, and column issues. Covers His-tag, GST-tag, and general affinity chromatography.
SDS-PAGE
Smiling bands, blank lanes, uneven migration, and staining problems. Covers gel casting, running conditions, and sample preparation.
9 Searchable Reference Tables
Amino acid table, codon table, restriction enzyme database, reagent reference, and more. The data you need mid-experiment, instantly, without leaving the app or searching the internet.
20 Amino Acids
Complete amino acid table with chemical structures, molecular weight, pI, pKa values, pH-dependent protonation states, per-moiety charge display, and an interactive pH slider.
5 Nucleotide Bases
Chemical structures, properties, and IUPAC degenerate codes.
64 Codons
Complete codon table with standard genetic code, fully searchable. Translate any codon to amino acid instantly.
132 Restriction Enzymes
Searchable restriction enzyme database covering Type II, IIS, nicking, and homing endonucleases with methylation sensitivity, star activity warnings, buffer info, and compatible end matching. Filter by type, overhang, or sort by name, site length, or buffer. Tap any enzyme to jump straight to a digest.
350+ Lab Reagents
MW, formula, CAS number, working concentrations, storage temperature, solubility, hazard warnings, and LD50 toxicity data for toxic reagents. Row and grid view toggle. Sort by name or molecular weight. Hazardous reagents link directly to the relevant lab safety guide.
20 Antibiotics & Selection Agents
Working concentrations, stock preparation, solvent, storage, resistance genes, and mechanism of action.
15 Media & Buffer Recipes
Scalable recipes for LB, SOC, SOB, TB, 2xYT, M9 minimal, PBS, TBS, TAE, TBE, SDS running buffer, transfer buffer, and Laemmli sample buffer with autoclave and supplement notes.
60 Fluorophores & Dyes
Excitation/emission wavelengths, visual spectrum bars, Stokes shift, applications, and laser line compatibility filter (405, 488, 532, 561, 633, 647 nm).
13 Gel Ladders & Dye Migration
6 protein and 7 DNA ladders with band sizes, prestain colours, mass per band, and loading volumes. Loading dye migration tables for bromophenol blue and xylene cyanol in agarose, denaturing PAGE, and SDS-PAGE.
Explore the Science
Articles about the science behind the tools. The principles, the context, and what BenchCalc does with them.
App in Action
Screenshots and video walkthrough. See BenchCalc running across calculators, troubleshooting, glossary, protocols, and more.
Latest Updates
Full version history. See what changed in v5.0.0 and every update since launch.
Science Games
Speed runs, memory challenges, and quizzes built from the science already in the app. Learn something or just have fun.
The Dilution Calculator
C1V1 = C2V2 explained properly. When to use serial dilutions, common mistakes, and why unit mismatches waste afternoons.
DNA Molarity from A260
Extinction coefficients, Beer-Lambert, purity ratios, and why getting molarity right matters for cloning.
Primer Melting Temperature
Nearest-neighbour vs basic methods, salt correction, primer pairs, and dimer checking.
Gel Electrophoresis
Choosing agarose percentages, loading dyes, migration tables, and picking the right ladder.
The Bradford Assay
Coomassie binding, standard curves, detergent interference, and when to use BCA instead.
The Bench Guide
414 glossary terms, 91 educational entries, lab safety, and practical tips. Why I built it and what is in it.
Troubleshooting Wizards
7 diagnostic wizards for Cloning, PCR, Restriction Digest, Agarose Gel, Protein Expression, Protein Purification, and SDS-PAGE. 87 questions, 252 solutions, real gel images.
Lab Safety
Why offline safety information matters, what is covered, and how it connects to everything else in the app.
Scientific Writing
Papers, theses, grants, posters, presentations, and reviewer responses. Why writing is part of doing science.
Lab Protocols
13 step-through protocols. Why they are different from a PDF and how they work at the bench.
Reference Tables
9 searchable tables including amino acids, codons, restriction enzymes, reagents with LD50 data, and gel ladders.
Built by a Scientist, for Scientists
Most lab calculator sites exist to show you ads. BenchCalc exists because I wanted something better.
No Ads. Actually.
Most lab calculator sites exist to monetise your attention. BenchCalc has no ads, no tracking, and no cookie banners. Just tools.
Works Fully Offline
Every tool, protocol, reference table, glossary entry, and safety guide works without internet. No connection required, ever.
Built at the Bench
BenchCalc was built by Dr Jason Woodgate (ORCID), a postdoctoral research associate at Newcastle University studying transcription-translation coupling in bacteria. I built this because I needed it, and because when I was discussing tRNA concentrations with my PhD student I had nothing better to point them to than an old website.
Pay Once, Own Forever
£1.19, one-time purchase. All 55 tools, the entire Bench Guide, all protocols, all reference tables, and all future updates. No subscriptions, no in-app purchases.
A Real App
BenchCalc is a native app for iOS and Android. Not a web wrapper and not a bookmarked website with a calculator bolted on.
No Data Collection
Zero analytics. Zero tracking. No account required. Your calculations, diagnoses, and setups stay on your device unless you choose to share them. Full control over data backups, deletions, and sharing.