Free Construction Calculators

Quick calculators for UK construction subcontractors. No sign-up required.

Retention Calculator

Calculate retention held and release dates for any UK construction contract. Enter a contract value, retention percentage, and practical completion date to see the total retention held, the 6+6 release schedule amounts, and exactly when each tranche is due back.

Retention Release Schedule Generator

Generate retention release dates and amounts from the retention already held on a contract. Supports 6+6, 12-month, and custom release schedules so subcontractors can forecast when retention cash should return after practical completion.

Payment Application Template Generator

Create a simple UK construction payment application summary with gross value, retention deducted, net due, previous certified value, and cumulative applied total. Built for subcontractors who need a quick template before moving to a live workflow.

Statutory Interest Calculator

Calculate the statutory interest and fixed compensation owed on overdue construction invoices and retention payments under the Late Payment of Commercial Debts (Interest) Act 1998. Shows daily interest at 8% above base rate plus the fixed £40, £70, or £100 compensation amount.

Profitability Calculator

Analyse project profit margins, convert between margin and markup, calculate break-even revenue, and benchmark your profitability against UK construction industry averages. Ideal for pricing subcontract tenders and reviewing completed project performance.

True Cost of an Employee Calculator

Work out what a PAYE employee costs per productive hour from gross pay, employer National Insurance, pension, paid holiday, and the hours they actually work.

CIS Deduction Calculator

Calculate CIS (Construction Industry Scheme) deductions on subcontractor payments. Enter the gross payment and materials cost to see the labour amount, the CIS deduction at 20% or 30%, and the net payment due. Instant results with no registration required.

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See Retention Management features or pricing plans from £49/month.