Skip to content
How Much Does It Cost?

Renovation budget calculator

A renovation almost never costs exactly what was quoted. Enter the items from your quotes, add a contingency cushion and any applicable tax, and you will have a realistic figure to decide on and finance the work.

Home improvement Updated:

Inputs

Line items

Example amounts: replace them with your own quotes.

$
$
$
$
$
$
%

Reserve for the usual surprises on site (old pipes, wiring…).

%

If amounts exclude tax, enter the rate that applies in your country.

Starting values are editable examples, not official prices. Results update automatically as you change the inputs.

Result

Renovation budget calculator — How Much Does It Cost?

Total budget

$7,480.00

Line items subtotal
$6,800.00
Contingency
$680.00
Taxes
$0.00
ItemAmount% of subtotal
Tiling and flooring$2,000.0029.4%
Carpentry$1,500.0022.1%
Plumbing$1,200.0017.6%
Electrical$1,000.0014.7%
Demolition and debris removal$600.008.8%
Painting$500.007.4%
Amount by item
Calculation breakdown
  1. Subtotal = sum of items = $6,800.00
  2. Contingency = $6,800.00 × 10% = $680.00
  3. Taxes = ($6,800.00 + $680.00) × 0% = $0.00
  4. Total = $7,480.00

Indicative result based on the data you entered. It does not replace a professional quote or your actual bill.

How it is calculated

Subtotal = sum of items. Contingency = subtotal × margin %.

Tax = (subtotal + contingency) × %. Total = subtotal + contingency + tax.

Worked example

Using the calculator’s example values:

  • Contingency margin: 10%
  • Applicable taxes: 0%
  • Line items: 6 example rows

Result: Total budget — $7,480.00 (line items subtotal: $6,800.00; contingency: $680.00; taxes: $0.00).

Money-saving tips

  • Ask for itemised quotes so you can compare them.
  • Check whether prices include tax, permits and debris removal.
  • The older the property, the larger the contingency it deserves.

Frequently asked questions

What contingency should I allow?

Many people use 10–20%; raise it for older homes or work on hidden services.

Are the example amounts market prices?

No. They only illustrate how it works. Replace them with your own quotes.

Can I save the budget?

Yes: use “Save PDF” to download it or “Share” to get a link with all your data.

How we calculate and the limits of the results: Methodology.

More home improvement calculators

Paint quantity calculator Litres or gallons and tins for walls and ceilings, minus openings. House painting cost calculator Paint, labour and supplies for the whole home. Tile calculator Tiles and boxes by size, joint and cutting allowance. Concrete and cement calculator Volume, cement bags, sand, gravel and water. Flooring cost calculator Laminate or wood boxes, underlay, skirting and labour.