UD5 Toolkit
Compression Sack Volume Calculator – Before & After Straps
Enter the loft of your clothes and the sack dimensions to see how small it gets when compressed. Pack more efficiently.
Tag: Calculator - Basic & Scientific
99+ toolsCliff Jump Safety Depth Calculator – Minimum Water Depth by Height
Enter the jump height to see the absolute minimum water depth recommended. Always check for submerged objects first.
PFD Buoyancy Checker – Is Your Life Jacket Enough for Your Weight?
Enter your body weight to see the minimum buoyancy (in lbs) your PFD should provide. Check the label on your vest.
Bear Bag Hang Calculator – Height, Branch Distance & Counterweight
Calculate the required rope length and branch height to properly hang a bear bag 12 ft high and 6 ft from the trunk.
Sawmill Log Length Optimizer – Maximize Usable Lumber
Enter your log diameter and target board dimensions to find the best bucking lengths to minimize waste.
Sternum Strap Height Finder – Prevent Shoulder Strap Slippage
Based on your torso length and pack size, find the optimal height for the sternum strap, usually just below the collarbone.
Flash‑to‑Bang Lightning Distance – Seconds to Miles/Km
Tap when you see the lightning and tap again when you hear thunder. The tool calculates the distance and advises if you're in the danger zone.
Multi‑Use Gear Savings Calculator – One Item, Many Jobs
List two items you plan to replace with one multi‑use item and see the weight and space saved. Simplify your pack.
Mosquito Net Drape Calculator – Achieve 360° Coverage
Enter your sleeping area dimensions to find the ideal suspension point height and line length so the net drapes without touching your skin.
WAG Bag Usage Calculator – How Many for Your Trip?
Based on the number of people and days, calculate how many waste alleviation and gelling bags to pack for a Leave No Trace trip.
Sleeping Bag Liner Temperature Boost Estimator
Select your sleeping bag's rating and add a liner to see how many extra degrees of warmth you gain. Extend your bag's range.
Hammock Structural Ridgeline Length – 83% Rule Calculator
Enter your hammock length to get the ideal fixed ridgeline length (83% of hammock length). Achieve a consistent, comfortable sag.
DIY Face Mask Recipe Calculator – Clay, Honey & Oil
Select your skin type and desired effect (detox, hydrate, calm) to get a simple recipe with exact proportions for a homemade face mask.
Calorie Density Calculator – Calories per Pound of Food
Enter the calories and weight of a food to see its calorie density. Choose foods with lower density to eat more and lose weight without hunger.
Subscription True Cost Calculator – Monthly to Annual
See the annual equivalent of all your monthly subscriptions. Convert weekly and monthly fees to a yearly total – you might cancel a few!
Rental Yield Calculator – Gross & Net Yield Percentage
Evaluate a rental property by entering purchase price and annual rent to instantly see gross and net rental yield. Factor in expenses for accurate ROI.
Plastic Footprint Calculator – How Much Ocean Plastic Do You Generate?
Answer a few questions about your weekly plastic usage and see an estimate of how much ends up in the ocean. Get reduction tips.
Semantic Versioning Range Intersection Finder
Enter two semver ranges (e.g., ^1.2.3 and >=1.2.4 <2.0.0) to see if they intersect and what the maximum satisfying version is.
Planted Tank Photoperiod Calculator – Prevent Algae
Based on your light intensity and CO2 level, get the recommended maximum hours of light per day to grow plants without an algae bloom.
Barbell Plate Calculator – Load Your Bar for Any Weight
Enter the target weight and the bar weight. The tool tells you exactly which plates to put on each side, using the fewest plates possible.
Newsletter Frequency Impact Calculator – Subscriber Churn Risk
See how changing your newsletter from weekly to daily (or vice versa) may affect open rates and unsubscribes based on industry benchmarks.
Cat Food Moisture Converter – Dry Matter Basis Calculator
Convert guaranteed analysis from 'as fed' to 'dry matter basis' to fairly compare protein, fat, and carbs between wet and dry cat foods.
GH & KH Hardness Ratio Calculator for Shrimp Tanks
Maintain the ideal calcium:magnesium balance for shrimp. Input your GH and KH to see the ratio and dosing recommendations for remineralizers.
Semantic Versioning Bump Calculator – What’s My Next Version?
Select the type of change (breaking, feature, fix) and your current version to see the next semantic version number and git tag suggestion.
Clothing Swap Event Calculator – Items to Bring per Person
Plan a clothing swap: estimate total items, rack space needed, and a fair bring‑vs‑take system based on guest count.
Board Game Storage Calculator – How Many Inches of Shelf?
Add your board game boxes and their dimensions to see total shelf feet needed. Plan your storage before your collection outgrows the Kallax.
Food Carbon Footprint Estimator – Compare Meals
Select common foods and portion sizes to see the CO₂ equivalent emissions. Compare a beef burger to a lentil soup and make greener choices.
Portrait Lighting Ratio Calculator – Key to Fill
Set your desired lighting ratio (2:1, 3:1, 4:1) and get the f‑stop difference between key and fill light for dramatic portrait effects.
Balloon Arch Calculator – How Many Balloons for Your Party?
Enter the arch width and height to estimate the number of balloons needed. Choose balloon size and pattern for a stunning decoration.
Shoelace Length Calculator – By Number of Eyelets & Lacing Style
Select the type of shoe and number of eyelet pairs to get the recommended lace length. Also supports bar lacing, criss‑cross, and runner's loop.
Omega‑3 Intake Calculator – EPA, DHA & ALA from Foods
Add your weekly servings of salmon, sardines, flax, chia, and walnuts to see your combined omega‑3 intake. Compare to the recommended 250–500 mg EPA+DHA.
Dietary Calcium Calculator – Am I Getting Enough?
Select the dairy, greens, and fortified foods you eat in a typical day to estimate your calcium intake. Compare to the RDA for your age and gender.
Floor Joist Span Calculator – Max Span for Lumber Size
Select wood species, lumber size, spacing, and load type to find the maximum allowable span. Reference for deck and floor framing.
RC & RL Filter Cutoff Frequency Calculator
Calculate the -3dB cutoff frequency for low‑pass and high‑pass RC and RL filters. Enter resistor and capacitor or inductor values.
Coaxial Cable Attenuation Calculator – dB Loss per 100 ft
Select a common coaxial cable type and frequency to see the signal loss in dB per 100 feet or meters. Plan your feedline with confidence.
Social Media Engagement Rate Calculator – By Platform
Calculate your engagement rate by impressions, reach, or followers. Compare to industry benchmarks to see if your content is performing well.
Surfboard Ding Repair Calculator – Resin & Cloth Quantity
Calculate the amount of epoxy or polyester resin and glass cloth needed to repair a ding based on its dimensions. Covers small cracks to delaminated areas.
Grow Light Distance Calculator – PAR & Foot‑Candles to Plant
Estimate the optimal hanging height of your grow light based on its PAR output and the light needs of your plants. Prevents light burn and leggy growth.
Kimchi & Pickle Salinity Calculator – Target 2–3% Salt
Calculate the amount of salt needed to achieve the ideal 2–3% salinity for vegetable ferments like kimchi or sauerkraut. Enter vegetable weight for a precise dry brine.
Rowing Calorie & Split Calculator – Concept2 Pace to Watts
Convert between rowing pace (per 500m), watts, and calories per hour. Plan your erg workouts with precise intensity targets.
pH Dilution Calculator – Adjust Acidity of Solutions
Calculate how much acid or base to add to achieve a target pH in a solution. Accounts for buffer capacity and initial volume.
Pediatric BMI Percentile Calculator – CDC Growth Charts
Calculate your child's BMI and see the age‑ and sex‑adjusted percentile using CDC growth charts. Understand whether your child is underweight, healthy, or overweight.
ASCVD Risk Estimator – 10‑Year Heart Disease & Stroke
Estimate your 10‑year risk of atherosclerotic cardiovascular disease using the Pooled Cohort Equations. Decide if statin therapy is recommended.
Skin Cancer Risk Calculator – Basal & Squamous Cell
Estimate your 5‑year risk of developing basal or squamous cell skin cancer based on age, sun exposure history, and skin type. Promotes early prevention.
Reptile Hide Size Calculator – Tight Fit for Security
Calculate the appropriate hide box dimensions based on your reptile’s length and girth. A snug hide reduces stress and promotes natural behavior.
Coffee to Water Ratio Calculator – Perfect Pour Over & French Press
Use the golden ratio for coffee brewing. Enter water volume or coffee weight to instantly get the right amount of grounds for your preferred strength.
Bird Seed Mix Calculator – Custom Feeder Blends
Create a custom bird seed blend by mixing ingredient percentages. Calculates total weight and helps attract specific bird species with the right nutrition.
Mulch Calculator – Coverage in Cubic Feet & Yards
Determine how much mulch you need by entering the area and desired depth. Converts between cubic feet, cubic yards, and the number of bags.
Artificial Turf Calculator – Square Footage & Rolls Needed
Measure your yard and calculate how many rolls or square feet of artificial grass you need. Includes waste factor for cuts and seams.
USD Inflation Calculator – Historical Buying Power
Find out what a dollar amount from a past year is worth today, or vice versa. Uses official US CPI data to show the true impact of inflation over time.
Bi‑Weekly Mortgage Payment Calculator – Save Thousands
Calculate the interest savings and earlier payoff date by switching to bi‑weekly mortgage payments instead of monthly. See the power of an extra annual payment.
Mega Millions Payout Calculator – Lump Sum vs Annuity
Calculate the after‑tax payout of a Mega Millions jackpot. Compare the lump‑sum cash value with the 30‑year annuity option, including federal and state tax estimates.
Canvas Wall Art Size Calculator – Proper Scale for Your Room
Determine the ideal canvas or framed art size for your wall. Based on furniture width and room dimensions, get the perfect proportion for a gallery-like look.
Recipe Cost Calculator – Price Per Serving & Ingredient
Add ingredients with purchase prices and quantities used to calculate the total cost of a recipe and cost per serving. Perfect for meal prepping on a budget.
Party Drink Calculator – Soda, Beer & Cocktails for Any Crowd
Plan the right amount of drinks for your party based on guest count and duration. Avoid running out or overspending on soda, beer, wine, and cocktails.
Wedding Playlist Time Calculator – Music for Ceremony & Reception
Build your wedding timeline by adding songs and their durations. See exactly how much music you need for cocktail hour, dinner, and dancing to schedule the perfect day.
Home Equity Loan & HELOC Payment Calculator
Estimate monthly payments and borrowing capacity for a home equity loan or line of credit. Input your home value, mortgage balance, and credit score range.
Early Auto Loan Payoff Calculator – Save on Interest
Calculate how much you'll save by paying off your car loan early. Add extra monthly or one-time payments and see the new payoff date and total interest saved.
Earned Value Management Calculator – EV, PV, AC, CPI, SPI
Monitor project performance with earned value analysis. Calculate EV, PV, AC, CPI, and SPI to see if your project is on budget and on schedule.
PERT Time Estimator – Optimistic, Most Likely & Pessimistic
Use the PERT (Program Evaluation Review Technique) formula to estimate task duration. Input optimistic, most likely, and pessimistic times to get a weighted average.