A 5 × 8 ft room with 8-ft walls has 187 sq ft of wall to paint — 1.07 gallons for two coats, so buy 1 gal + 1 qt (about $80.63).
| Surface | Area (sq ft) | Coats | Need | Buy | Cost |
|---|---|---|---|---|---|
| WallsTypical latex wall paint · 350 sq ft/gal | 187 | 2 | 1.07 gal | 1 gal + 1 qt | $80.63 |
| Option | Cans | Leftover | Cost |
|---|---|---|---|
| Cheapest mix | 1 gal + 1 qt | 0.18 gal | $80.63 |
| Gallons only | 2 gal | 0.93 gal | $115 |
Online prices checked October 23, 2026 (Sherwin-Williams, Benjamin Moore, Walmart). Tap any price to enter your store's.
| Plan | Gallons | Buy | Paint cost |
|---|---|---|---|
| Walls, 1 coat (same-color refresh) | 0.53 | 1 gal walls | $57.59 |
| Walls, 2 coats | 1.07 | 1 gal + 1 qt walls | $80.63 |
| Walls + ceiling, 2 coats | 1.3 | 1 gal + 1 qt walls + 1 qt ceiling | $104 |
| Walls + ceiling + trim | 1.3 | 1 gal walls + 1 qt ceiling + 1 qt trim | $104 |
| New drywall: primer + 2 coats | 1.69 | 1 gal + 1 qt walls + 1 gal primer | $105 |
| Deep color, no primer (3 coats) | 1.6 | 2 gal walls | $115 |
A 5×8 full bath has little paintable wall once the tub surround and vanity are out — enter the tiled area in “Wall hidden by cabinets, tile or built-ins” (a 5-ft tub tiled to 6 ft hides 30 sq ft). Use a satin or semi-gloss bath paint.
The full method, material data and tips are on the main paint calculator page.