Academics.
1 calculatorExam scoring, rubrics, and the weighted math behind the number you actually get.
Power.
4 calculatorsBatteries, solar, and the electrical math behind everything off-grid.
Battery
Runtime
How long a battery will actually power your load, with Peukert correction for lead-acid.
Open calculator →Amp Hours
Needed
Size a battery bank from your loads, runtime, and days of autonomy.
Open calculator →Amp-Hour
Conversions
Convert between watts, amps, capacity, and runtime in one place.
Open calculator →Solar Panel
Sizing
Size an array from daily energy, sun hours, and battery storage, for off-grid, RV, or backup.
Open calculator →Finance.
4 calculatorsPaychecks, rent, taxes, tips, and the math behind qualifying for things.
Take-Home
Pay
Net paycheck after federal, state, FICA, and pre-tax deductions. 2026 brackets.
Open calculator →Tip
Calculator
Tip math and bill splitting for any party size, with round-up and pre-tax options.
Open calculator →NYC 40×
Rent Rule
Does your income clear the 40-times threshold landlords look for?
Open calculator →Arizona
Sales Tax
Retail TPT math with state, county, and city rates baked in.
Open calculator →Body.
8 calculatorsHealth, sleep, due dates, and what's still in your system.
Pregnancy
Due Date
Estimated delivery date from LMP, conception, ultrasound, or reverse, with milestones.
Open calculator →Sleep
Cycle
Best wake times and bedtimes based on 90-minute sleep cycles.
Open calculator →Blood Alcohol
Estimator
BAC from drinks, weight, sex, and time, with time-to-sober projection.
Open calculator →Caffeine
Half-Life
How much caffeine is still in your system, hour by hour, after every cup.
Open calculator →Testosterone
Dosage
Convert a prescribed dose to millilitres and syringe units, with ester weight and peak-to-trough swing.
Open calculator →Free
Testosterone
Free and bioavailable testosterone from total T, SHBG and albumin, via the Vermeulen equation.
Open calculator →Concentrate
to Edibles
Concentrate to mg per gummy, or backwards from a target dose, with decarb and infusion losses.
Open calculator →Drug Test
Detection Times
Estimated urine, blood and hair windows for six substances, weighted by how often you used.
Open calculator →Peptides.
27 calculatorsVial math, one peptide at a time. Concentration, syringe units, and where each one stands with the FDA.
Peptide
Reconstitution
Concentration, dose volume and syringe units after adding bacteriostatic water to a vial.
Open calculator →Semax
Dosage
Syringe units for a semax vial, with the 1,000 and 7,500 mcg/mL strengths the FDA reviewed.
Open calculator →Thymosin
Alpha-1
Vial to syringe units for thymosin alpha-1, and how the FDA's committee voted on it.
Open calculator →Ipamorelin
Dosage
Syringe units for an ipamorelin vial, checked against the 2,000 mcg/mL strength the FDA reviewed.
Open calculator →MOTS-c
Dosage
Syringe units for the 5 mg and 10 mg MOTS-c vials the FDA reviewed, at any amount of water.
Open calculator →DSIP
Dosage
Syringe units for a DSIP vial, checked against the 1,000 mcg/mL strength the FDA reviewed.
Open calculator →Epitalon
Dosage
Syringe units for an epitalon vial, with the 3,000 mcg/mL and 10 mg/mL strengths the FDA reviewed.
Open calculator →AOD-9604
Dosage
Syringe units for an AOD-9604 vial, checked against the 1,200 mcg/mL strength the FDA reviewed.
Open calculator →Cagrilintide
Dosage
Syringe units for a cagrilintide vial at any amount of water, with what the FDA says about it and what the trials tested.
Open calculator →GHK-Cu
Dosage
Syringe units for a GHK-Cu vial, and where the FDA's compounding record stood on injections as of May 2026.
Open calculator →IGF-1 LR3
Dosage
Syringe units for an IGF-1 LR3 vial at any amount of water, and what the published record does and doesn't say about it.
Open calculator → View all 27 →Build.
3 calculatorsConstruction, repair, and the geometry of getting things straight.
Concrete
Volume
Cubic yards needed for slabs, columns, and post holes, plus bags, trucks, and cost.
Open calculator →Stair
Stringer
Risers, treads, total run, stringer length, and IRC code check for any rise.
Open calculator →Gutter
Slope
Total drop and end heights for a properly pitched gutter run.
Open calculator →Farm.
5 calculatorsLivestock, agriculture, and the schedules around growing things.
Chicken
Hatching
21-day incubation timeline for chicken eggs. Candling, lockdown, and hatch milestones.
Open calculator →Guinea Fowl
Hatching
28-day incubation timeline for guinea fowl eggs. Tailored to the species' thick shells and humidity needs.
Open calculator →Turkey
Hatching
28-day incubation timeline for turkey eggs. Same schedule for wild, heritage, and Broad Breasted.
Open calculator →Emu
Hatching
52-day incubation timeline for emu eggs, with the weekly weight-loss targets that replace candling.
Open calculator →Hog
Gestation
Farrowing date from breeding date, or run it the other way around.
Open calculator →Shop.
2 calculatorsTools, fluids, mixing ratios, and the workshop arithmetic that keeps engines alive and bottles labelled right.
Speed.
2 calculatorsVehicles, fuel cost, and the power-to-weight math of going fast.
Sport.
2 calculatorsRunning pace, jumps, reach, and what it takes to clear a target.