Know the right size before you buy.
Free guided calculators for generators, power stations, trailers, air compressors, concrete, gravel, paint, flooring, heat, pumps, cords, shop equipment, and more.
New: home improvement cost range estimator
Estimate realistic planning ranges for bathroom remodels, basements, decks, painting, flooring, kitchens, roofs, tile showers, and drywall repairs. The tool breaks out major cost drivers instead of pretending every project has one exact price.
Printable quote checklists and planning worksheets
Use the cost estimator to set a planning range, then use printable worksheets to compare contractor quotes by scope, allowances, exclusions, schedule, payment terms, and hidden-cost risks.
Quote comparison worksheet
Compare up to three contractors by what is included, what is excluded, and what still needs clarification.
Open worksheet →Deck quote checklist
Check framing, footings, railing, stairs, demo, permits, and hidden ledger/siding issues before comparing deck quotes.
Open checklist →Project budget planner
Track target budget, must-haves, allowances, contingency, and decisions before requesting quotes.
Open planner →Popular calculators
Start with the practical tools people are most likely to need first: concrete bags, extension cords, wall R-value, generator sizing, square footage, and roofing materials.
Concrete Bags
Estimate how many concrete bags you need from slab length, width, thickness, bag yield, waste allowance, and common small-project dimensions.
Open calculator → Power & BackupExtension Cord Voltage Drop
Estimate extension cord voltage drop from one-way cord length, amps, voltage, and AWG wire gauge for tools, chargers, generators, pumps, and temporary power.
Open calculator → Home & BasementWall Assembly R-Value
Estimate whole-wall R-value including wall dimensions, cavity insulation, wood studs, drywall, sheathing, and continuous foam insulation.
Open calculator → Power & BackupHome Generator Size
Estimate backup generator size for home essentials, standby generator planning, running watts, startup surge, well pumps, sump pumps, refrigerators, and outage loads.
Open calculator → Geometry BasicsSquare Footage
Calculate square footage or square meters for rooms, floors, walls, slabs, yards, decks, flooring, paint, tile, and project material estimates.
Open calculator → Materials & ProjectsShingle Bundles
Estimate roof shingles and bundles from building footprint, roof pitch, bundle coverage, overhang, extra roof areas, and waste allowance.
Open calculator →Designed for normal people, not spec sheets.
Each calculator uses plain-English inputs, common presets, clear units, Imperial/Metric switching where useful, and optional advanced settings. You can start with what you know, then refine the estimate if you have exact ratings.
Start with the number you actually know.
Many calculators ask for a final area, load, or material quantity that most people do not already know. RightSizeTools is built the other way around: enter the measurements, equipment, or situation you have, then let the calculator estimate the useful planning number.
Clear measurements
- Fields are labeled with units.
- Visual guides show which dimension goes where.
- Imperial and metric modes are supported where useful.
Practical defaults
- Common thicknesses, waste factors, and coverage values are built in.
- Advanced settings stay available without overwhelming the main form.
Real-world checks
- Results include notes, mistakes to avoid, and reminders to verify labels, ratings, and local requirements.
Popular project paths
These paths connect the calculator, guide, cost estimator, and printable checklist for the jobs people are already searching for.
Planning a roof?
Estimate shingles, underlayment, pitch, replacement cost, and print a roofing quote checklist.
Open roofing calculators →Planning a deck?
Estimate deck cost, boards, concrete for footings, square footage, and quote scope.
Open deck calculators →Planning insulation?
Estimate insulation packages, whole-wall R-value, comfort sizing, and moisture-related planning.
Open insulation calculators →Focused calculator hubs
Use topic hubs when one calculator is not enough. They connect the relevant tools, guides, and printable worksheets.
Roofing Calculators
Estimate roof shingles, roofing squares, underlayment rolls, roof pitch, roof replacement cost, and quote checklist items before comparing roofing estimates.
Open hub → Project pathDeck Calculators
Estimate deck cost, deck railing cost factors, deck boards, concrete bags for footings, square footage, and quote-template items for new decks and replacements.
Open hub → Project pathConcrete Calculators
Estimate concrete bags, gravel under concrete slabs, paver base, square footage, material depth, waste, tons, yards, and planning quantities.
Open hub → Project pathPower Calculators
Estimate backup generator size, standby generator sizing, portable power station runtime, 12V battery runtime, extension cord voltage drop, and backup-power loads.
Open hub → Project pathProject Cost Calculators
Estimate remodel cost ranges, compare contractor quotes, print planning checklists, and understand what should be included before requesting estimates.
Open hub → Project pathInsulation Calculators
Estimate insulation quantity, whole-wall R-value, comfort sizing, and basement moisture planning.
Open hub →Calculator categories
Choose a category to see only the tools for that kind of project or buying decision.
Power & Backup
5 calculators
View this category → CategoryTowing & Trailers
2 calculators
View this category → CategoryHome & Basement
10 calculators
View this category → CategoryWorkshop & Tools
3 calculators
View this category → CategoryMaterials & Projects
17 calculators
View this category → CategoryGeometry Basics
9 calculators
View this category →