Free Roofing Calculators
Measure it right the first time.
Trusted by homeowners, contractors, and roofers
Measurement
Roof Area Calculator
Calculate total roof area from building dimensions and pitch. Get results in square feet and roofing squares for any roof type.
Roof Pitch Calculator
Find your roof pitch from rise/run measurements. Shows pitch as ratio, degrees, and percentage with walkability rating.
Rafter Length Calculator
Calculate rafter length from span and pitch. Includes overhang, birdsmouth cut depth, and total rafters needed with spacing.
Materials
Shingle Calculator
Calculate how many shingle bundles you need for your roof. Accounts for waste factor and provides cost estimates by shingle type.
Metal Roofing Calculator
Calculate metal roofing panels, ridge caps, and screws needed. Supports common panel widths with overlap and cost estimates.
Underlayment Calculator
Calculate how many rolls of roofing underlayment you need. Supports felt and synthetic types with overlap adjustments.
Ice & Water Shield Calculator
Calculate ice and water shield membrane needed for eaves, valleys, and penetrations. Based on climate zone requirements.
Cost & Planning
Roofing Material Cost Estimator
Estimate total roofing project costs including materials, labor, and tear-off. Compare prices across material types and regions.
Gutter Length Calculator
Calculate total gutter length, downspouts, end caps, corners, and hangers needed for your home with cost estimates.
Roof Ventilation Calculator
Calculate required attic ventilation per building code. Get balanced intake and exhaust recommendations with NFA calculations.
Guides
Why Use roofmath.dev?
Instant Results
Results update live as you adjust inputs. No waiting, no submit buttons.
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Print Your Estimates
Print results to share with your contractor or keep for your records.