Renovation cost calculator

How to use the renovation budget planner

Build a renovation budget from editable line items or start with a cost-range preset. Compare low, mid and high estimates, then track actual spending against each line.

1. Choose a Project preset, enter the project Size, and select a Finish level.
2. Adjust the Regional index if local quotes differ from the preset range.
3. Click Add lines or Replace all lines, then edit each category, description, quantity and cost range.
4. Enter Contingency and Sales tax percentages. Turn on the tax option if sales tax should include contingency.
5. Add Actual paid (line) amounts as invoices or quotes arrive, then review totals and variances.
6. Use the available tool actions to print, export, share or reset the budget.

What to enter

Project preset

Choose a starting scope such as a bathroom, kitchen, flooring, painting or roof project. The default is Bathroom · Full bath refresh (cosmetic).

Size (sq ft) / Size (roofing squares)

Enter the area used by the selected preset. The default preset starts at 40 sq ft. Roofing presets use squares, where 1 square equals 100 sq ft of roof surface.

Finish level

Choose Economy, Mid-range or Premium. The default is Mid-range. Preset components that vary by finish use multipliers of 0.8, 1.0 or 1.4.

Regional index (optional)

Use your own factor for local conditions. It defaults to 1.0, accepts 0.3 through 3.0 in 0.05 steps, and scales all preset components. Leave it at 1.0 if unsure.

Budget name

Name the budget for the page, printout or export. The default is My renovation.

Category

Group a line such as Fixtures, Labor or Materials. Blank categories appear as Uncategorized in category summaries.

Description

Describe the work or purchase for this line. Preset descriptions can be edited.

Qty

Enter the number of units. A new custom line starts at 1. Preset fixed items use 1, while per-unit items use the selected Size. Zero is allowed.

Unit

Enter a label such as ea, sq ft or square. A new custom line starts with ea.

Unit cost low

Enter the lower unit cost in US dollars. Preset values fill this from the selected range; a new line starts at $0.

Unit cost high

Enter the upper unit cost in US dollars. Preset values fill this from the selected range; a new line starts at $0.

Actual paid (line)

Optionally enter the amount actually paid for the whole line. Leave it blank until you have an amount to compare.

Contingency

Set the contingency percentage applied to each estimate subtotal. The default is 15%, with an allowed range of 0% to 100%.

Sales tax

Enter a sales tax percentage from 0% to 30%. The default is 0%. Tax applies to the subtotal unless the tax-on-contingency option is selected.

Apply sales tax to contingency

When selected, sales tax is calculated on the subtotal plus contingency. It is off by default.

Target budget

Enter a target in US dollars to compare with the mid estimate and actual total. The default is $0, which shows no target progress.

Example: full bath refresh with 8% sales tax

Start with the default Full bath refresh preset at 40 sq ft, Mid-range finish and a 1.0 regional index. The four preset lines are Fixtures at $1,500–$5,000, Flooring and wall finishes at $20–$60 per sq ft, Lighting at $400–$1,500, and Installation labor at $3,000–$8,000. The finishes line calculates as $20 × 40 = $800 low and $60 × 40 = $2,400 high. The low subtotal is $1,500 + $800 + $400 + $3,000 = $5,700. The mid line amounts are ($1,500 + $5,000) ÷ 2 = $3,250, ($800 + $2,400) ÷ 2 = $1,600, ($400 + $1,500) ÷ 2 = $950 and ($3,000 + $8,000) ÷ 2 = $5,500, for a mid subtotal of $11,300. The high subtotal is $5,000 + $2,400 + $1,500 + $8,000 = $16,900. With 15% contingency, the amounts are $5,700 × 15% = $855, $11,300 × 15% = $1,695 and $16,900 × 15% = $2,535. Set Sales tax to 8% and leave tax on contingency off. Tax is $5,700 × 8% = $456 low, $11,300 × 8% = $904 mid and $16,900 × 8% = $1,352 high. The resulting totals are $5,700 + $855 + $456 = $7,011 low, $11,300 + $1,695 + $904 = $13,899 mid and $16,900 + $2,535 + $1,352 = $20,787 high.

How the budget is calculated

Each line calculates a low and high amount by multiplying its unit cost by Qty. For a preset, fixed components are used once, while per-unit components are multiplied by the selected Size. The Finish level scales components marked as finish-sensitive: Economy uses 0.8, Mid-range uses 1.0 and Premium uses 1.4. The Regional index scales every preset component. Low and high line amounts are rounded to whole cents. The line mid amount is the rounded midpoint between that line's low and high amounts, and the mid subtotal is the sum of the line mid amounts. Contingency is the selected percentage of each subtotal. By default, tax is the selected percentage of the subtotal only. If Apply sales tax to contingency is selected, tax uses the subtotal plus contingency instead. Each percentage result is rounded to whole cents, then added to the subtotal. If the high cost is entered below the low cost, the calculator orders the resulting range from low to high.

Reading the results

The Estimated total (mid) uses the sum of line mid amounts, contingency and tax. The displayed Range shows the corresponding low and high totals. The subtotal, contingency, tax and total rows show low and high values; line and print views can show cents, while the large estimated total uses whole-dollar formatting. Actual is the sum of Actual paid (line) amounts that have been entered. It does not add estimates for blank actual fields and does not add contingency or tax. For each line, Under means actual paid is below the low estimate, In range means it falls from low through high, and Over means it exceeds the high estimate. The variance amount compares actual paid with that line's mid estimate. If a Target budget is entered, progress compares the mid total and actual total with that target; a target of $0 shows 0% progress.

Limitations and common mistakes

• Preset ranges are editable planning defaults, not quotes. They are marked as typical US ranges for 2026 and can vary by region and finish; use local quotes for project decisions.
• Size is interpreted according to the selected preset. Some presets use floor area or wall area as a proxy, and roofing uses roof surface squares rather than building footprint.
• Sales tax is not detected automatically. Enter the percentage yourself and choose whether it applies to contingency.
• Actual totals include only lines with an Actual paid (line) value. They are not a completed project total unless you enter every relevant actual amount.

Frequently asked questions