TryBuildCalc

Paint Calculator for 1000 Sq Ft (Interior & Exterior Paint Quantity)

Estimate paint quantity, coats, wastage, and cost.

Inputs

Section 1: Wall & Surface

ℹ️Use wall length & height if you'd rather let the calculator work out the area, or enter a known wall area directly.

Multiple Walls (e.g. Accent Wall + Main Walls)?

ℹ️Paired with Opening Width below to size a door/window on this wall — leave both blank if there are none. Unit is independent of the wall's own length/height unit.

ℹ️Multiplied by Opening Length to get the deducted area.

ℹ️Adjusts the suggested coverage rate by up to ±30% for how much paint the surface absorbs.

ℹ️Auto-suggested from Paint Type and Surface Condition — still editable.

Include Primer Coat?

ℹ️Drives the suggested wastage allowance below — spray loses more to overspray than a roller.

ℹ️Auto-suggested from Application Method and Surface Condition — still editable.

Section 2: Can Size & Cost

ℹ️Check your product's label — common sizes are 1, 4, 10, and 20 liters.

Common can sizes

Enable Cost Estimation?

Recommended paint: 16.26 L (4.30 gal) (2 cans)

Net Paintable Area: 92.90 m²

Paint Summary

Gross Wall Area: 92.90 m²

Net Paintable Area: 92.90 m²

Topcoat (before wastage): 15.48 L (4.09 gal)

+ Wastage (5%): 0.78 L (0.21 gal)

Topcoat Required: 16.26 L (4.30 gal)

Cans & Purchase

Recommended Paint: 16.26 L (4.30 gal) total

Topcoat Cans: 2 cans

Total Cans: 2 cans

Quick Insight

Buy at least 16.26 L (4.30 gal) (2 cans) from the same production batch to avoid colour or shade mismatch.

Calculated from wall area, paint coverage, and number of coats.

Assumptions Used

Net area from gross wall area minus openings, coverage-adjusted for paint type and surface condition | Cans rounded up to the next whole can.

Bill of Materials

Main material: 2 cans + recommended tools

+

Computed items reflect your entered wall dimensions and paint details; consumables below are general recommendations — actual needs vary by product and site.

For Your Job

Topcoat Paint

2 cans

16.26 L total

General Tools & Consumables

Paint roller & tray

tool

Paintbrush (cutting-in)

tool

Masking tape

consumable

Drop cloths / floor sheeting

consumable

Sandpaper (fine grit)

site-dependent

Approximate results for planning only. Verify with a professional.

Painting a whole room instead of a few walls?Use the Room Paint Calculator to estimate all four walls together from room length/width, with per-opening deductions and an optional ceiling.
Haven't puttied these walls yet?Use the Wall Putty Calculator to estimate the base coat that goes on before primer and this topcoat.
Paint Wall Visualization2 Coats applied with rollerLength: 100 ftHeight: 10 ftDiagram simplified for clarity (not to scale)

Looking for the verification checklist, reference tables, or tips and mistakes?See the complete Paint Calculator.

Paint estimate for 1000 sq ft of wall

This page uses a 100 ft x 10 ft wall — almost exactly 1000 sq ft (92.9 m²) — at 12 m²/L interior coverage, needing 15.48 liters raw for 2 coats, or about 16.26 liters after 5% wastage, rounding up to 2 cans of 10 L.

1000 sq ft is a common round figure for pricing out a whole house's exterior or a large open-plan interior area — this page shows it as one continuous wall for simplicity; a real 1000 sq ft job is usually several separate walls, which Multiple Walls mode can model with each wall's own opening deductions.

  • Wall: 100 ft x 10 ft (~1000 sq ft, 92.9 m²).
  • Coverage: 12 m²/L, 2 coats.
  • Cans: 2 (10 L each).

How paint calculation works

Step 1 — Net paintable area

Gross Area = Length x Height Net Area = Gross Area - Openings Area

Openings (doors, windows, fixed units) are optional — leave blank to paint the full gross area.

Step 2 — Topcoat requirement

Topcoat = (Net Area / Coverage) x Coats

Coverage is auto-suggested from Paint Type and Surface Condition, and always overridable.

Step 3 — Primer requirement (optional add-on)

Primer = Net Area / Primer Coverage

Calculated separately from the topcoat and added alongside it — not chosen instead of it — since primer and topcoat are different products bought in their own cans.

Step 4 — Add wastage allowance

Final Topcoat = Topcoat x (1 + Wastage / 100) Final Primer = Primer x (1 + Wastage / 100)

Wastage is auto-suggested from Application Method and Surface Condition (5% roller, 7% brush, 12% spray, bumped further for a rough surface or multiple walls), and covers roller/brush losses, spillage, and tray residue.

Step 5 — Convert to cans

Cans = ROUND UP(Final Liters / Can Size)

Topcoat and primer cans are rounded up separately, since they're different products.

Real-World Paint Calculation Example

This example uses the active inputs above and follows the same steps from the formula section.

Input Values Used

InputValueWhy it is used
Wall size100 ft x 10 ftDetermines whether gross area comes from length x height or a direct entry
Paint Type / Surface ConditionInterior Emulsion (~12 m²/l) / Standard new putty/plaster finishSets the auto-suggested coverage rate below
Coverage x Coats12 m²/liter x 2Converts net area into raw topcoat liters
Application Method / WastageRoller / 5%Adds allowance for roller/brush loss and spillage before rounding to cans
PrimerOffAdds a separate primer line alongside the topcoat when switched on
Can size / Cost estimation10 L / OffRounds final liters to whole cans, and prices them when enabled

Step 1 — Net Paintable Area

CalculationFormula / SubstitutionResult
Gross area100 ft x 10 ft92.9
Net paintable areaNo openings deducted92.9

Step 2 — Topcoat Requirement

CalculationFormula / SubstitutionResult
Raw topcoat(92.9 ÷ 12) x 2 coats15.48 liters
Final topcoat (incl. wastage)15.48 x (1 + 5%)16.26 liters

Step 3 — Cans

CalculationFormula / SubstitutionResult
Topcoat cansROUND UP(16.26 ÷ 10 L)2 cans
Total cansTopcoat cans2 cans

Therefore, for a 92.9 m² wall with 2 coats, you need 16.26 liters of paint, or 2 cans.

Actual paint consumption may vary depending on surface condition, paint quality, application method, and wall preparation. For a full room, switch on Multiple Walls and add each wall as its own row.

This page keeps things focused on the calculation above. For the full construction guide — verification checklist, reference tables, usage steps, tips, common mistakes, and limitations.See the complete Paint Calculator.

Disclaimer: This calculator provides approximate results for planning and estimation purposes only. Actual requirements may vary based on site conditions, materials, workmanship, and local building regulations. Always consult a qualified engineer, architect, or construction professional before making final decisions.

FAQ

About 16.26 liters, rounded up to 2 cans of 10 L. 1000 sq ft (100 ft x 10 ft) converts to 92.9 m²; at 12 m²/L coverage and 2 coats that's 15.48 liters raw, which becomes 16.26 liters after 5% wastage.
It's a simplification for a quick estimate — a real 1000 sq ft job is almost always several separate walls with doors and windows. Switch on Multiple Walls to enter each wall separately with its own opening deductions for a more accurate total.