Coating Calculator - Expanded Tools
Accurate and simple painting & coating calculators
Dry Film Thickness (DFT) Calculator
Coating Cost Calculator
Wet Film Thickness (WFT) Calculator
Paint Quantity Calculator
Surface Area Calculator
Paint Coverage Calculator
Spreading Rate Calculator
Paint Consumption Calculator
Paint Cost Calculator
Volume Solids Calculator
Drying Time Calculator
Thickness Calibration Calculator
VOC Content Calculator
Pot Life Calculator
Surface Profile Calculator
Adhesion Test Calculator
Film Hardness Calculator
Color Coverage Calculator
Dew Point Calculator
Relative Humidity Calculator
Mixing Ratio Calculator
Coat-Weight Calculator
Holiday Detector (Test Voltage) Calculator
Screen Coating Usage Estimator
Varnish Coverage Calculator
Foil Method Dry Coat-Weight
Applied Coat-Weight (Anilox)
Surface Profile Gauge Tool
Film Thickness Gauge Tool
Material Fit & Adhesion Suitability
Paint Waste Estimator
Pipe Surface Area Calculator
Cylindrical Tank Surface Area Calculator
Calculates the paintable surface area of a vertical cylindrical tank.
Spherical Tank Surface Area Calculator
Calculates the paintable exterior or interior surface area of a spherical tank.
I-Beam Surface Area Calculator
UV/EB Coating Calculator
Primer/Adhesive Quantity Calculator
Tip Size for Spray Painters
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Coating Calculator: Your Complete Guide to All 37 Free Painting & Coating Tools
If you’ve ever stood in front of a wall, a tank, or a steel beam wondering exactly how much paint you’ll need—or how thick that coat should be—you’re not alone. That’s why I built the Coating Calculator. It’s a completely free online toolset with 37 practical calculators that take the guesswork out of painting and coating jobs, whether you’re a professional contractor, an industrial painter, or just tackling a weekend project at home.
The best part? It works in both metric and imperial units (flip a switch and everything updates instantly), there’s no sign-up, no app to download, and it runs perfectly on your phone right on the job site.
This guide walks you through every single tool, explains what it does, and shows when you’ll actually use it in the real world. Let’s dive in.
Dry Film Thickness (DFT) & Wet Film Thickness (WFT)
These two are probably the most-used tools on the site.
Dry Film Thickness (DFT) Calculator You measure the wet paint with a comb gauge, enter the reading (microns or mils) plus the paint’s volume solids percentage, and it tells you the final dry thickness. Perfect for checking if you’re hitting the spec on protective coatings.
Wet Film Thickness (WFT) Calculator Working the other way: tell it the target dry thickness and solids %, and it says exactly how thick to lay the paint while it’s still wet. Painters love this one because it stops them from applying too little (and risking corrosion) or too much (wasting money).
Paint Quantity, Coverage & Cost Tools
These save you from running out of paint halfway through a job—or buying way too much.
Paint Quantity Calculator Enter the surface area, the paint’s coverage rate, and how many coats you plan—it spits out the exact liters or gallons needed.
Paint Coverage Calculator Got a few cans already? Plug in the volume and coverage rate to see how much area they’ll handle.
Paint Consumption Calculator Quick check of how much paint you typically use per square meter or foot.
Paint Cost Calculator Simple but handy: quantity × price per unit = total spend.
Paint Waste Estimator Realistic adjustment for overspray or roller loss (30% for airless spray, 15% roller, 10% brush). Buy what you’ll actually use.
Coating Cost Calculator My favorite for bigger jobs. It factors in paint, multiple coats, number of pieces, monthly equipment and utility overheads, plus consumables. Gives you a true cost-per-piece figure—great for quoting and staying profitable.
Surface Area for Tricky Shapes
Flat walls are easy. These handle the awkward stuff.
Basic Surface Area Calculator Length × width for floors, walls, panels.
Cylindrical Tank Surface Area Sides plus optional top/bottom caps, interior or exterior—ideal for storage tanks.
Spherical Tank Surface Area Full surface area for spherical vessels.
I-Beam Surface Area Structural steel beams: just enter length, depth, flange width, and web thickness.
These four tools alone have saved industrial painters hours of manual math.
Thickness, Profile & Coat-Weight Tools
Spreading Rate – theoretical coverage from volume and target DFT. Thickness Calibration – correct your gauge against a known standard. Film Thickness Gauge Tool – apply that calibration on-site. Surface Profile Calculators – average blast profile from min/max readings (key for adhesion). Foil Dry Coat-Weight – gravimetric dry weight using foil samples. Anilox Coat-Weight – predicts applied weight in flexo printing.
All built for real-world quality checks.
Environmental Tools
Drying Time – rough estimate from temperature and humidity. Dew Point – avoid painting when condensation risk is high. Relative Humidity – from vapor pressure readings. VOC Content – stay compliant with regulations.
Paint in the wrong conditions and you’re asking for blisters or peeling. These help you pick the right day.
Adhesion & Hardness
Adhesion Test Interpreter – turns a 1–10 score into plain English. Film Hardness Checker – pencil test + cure time = pass/fail. Fit & Adhesion Suitability – quick compatibility between substrate and coating type.
Catch problems early instead of after the coating fails.
Mixing & Pot Life
Mixing Ratio – perfect ratios for two-part epoxies and polyurethanes. Pot Life – how long you have before the mix goes off.
No more ruined batches.
Specialty & Industrial Tools
Coat-Weight – general gravimetric method. Holiday Detector Voltage – safe voltage suggestion for pinhole testing. Varnish Coverage – adjusts for substrate absorbency. Screen Coating Usage – ink estimate from mesh and impressions. UV/EB Coating – coverage for fast-cure systems. Primer/Adhesive Quantity – exact amount for prep coats. Tip Size for Spray Painters – decode tip codes or find matches by orifice size.
These are the ones printers, coaters, and spray techs keep bookmarked.
Extra Precision Tools
Color Coverage – accounts for opacity. Volume Solids – true solids content by volume.
Why I Love This Toolset (and Why Users Keep Coming Back)
- 37 genuinely useful tools in one place
- Completely free—no ads, no paywalls, no accounts
- Instant unit switching (metric ↔ imperial)
- Works great on phones—use it on scaffolding or in the shop
- Updated regularly with real user feedback
How to Get Started
Just click the tool you need from the top menu, enter your numbers, hit Calculate. Results appear instantly.
Most popular starting points:
- Thickness problems → DFT or WFT
- Buying paint → Paint Quantity + Waste Estimator
- Tanks or steel → Cylindrical, Spherical, or I-Beam
- Weather worries → Dew Point or Drying Time
- Spray setup → Tip Size tool
Frequently Asked Questions
How accurate are the calculations? They use the same industry-standard formulas found in manufacturer data sheets and standards like ASTM and ISO. Thousands of pros use them daily.
Do I need an account or app? Nope—just open the page in any browser.
Will it work on my phone? Yes, fully mobile-friendly.
Metric or imperial? Both—one click switches everything.
Good for heavy-duty or marine work? Definitely—many tools were built specifically for protective and industrial coatings.
Final Thoughts
After years of watching painters and coaters wrestle with spreadsheets, scribbled notes, and rough guesses, I put all these tools together in one clean, free place. The Coating Calculator really is the most complete set of 37 painting and coating tools you’ll find online in 2026.
Give it a try on your next job—you’ll save time, cut waste, and end up with better-looking, longer-lasting results.