Free UK Tech & SaaS Calculators 2026
MRR forecasting, churn analysis, SaaS valuation, Rule of 40, Stripe fees and AWS cost estimators — built for UK founders and SaaS finance teams. Free to use, no account needed.
MRR / ARR Forecast Calculator
Project MRR and ARR growth: new bookings, expansion, contraction and churn over 24 months.
Churn Cohort Calculator
Analyse logo churn and revenue churn by cohort — monthly and annual views.
SaaS Valuation (ARR Multiple)
Estimate your SaaS company's valuation based on ARR, growth rate, Rule of 40 and NRR.
Rule of 40 Calculator
Check if your SaaS business meets the Rule of 40 — revenue growth rate + EBITDA margin ≥ 40%.
CAC Payback Period Calculator
How many months to recover your Customer Acquisition Cost from gross margin.
Net Dollar Retention (NDR) Calculator
Calculate NDR from expansion, contraction and churn — benchmark against SaaS cohort medians.
SaaS Magic Number Calculator
Efficiency of your sales and marketing spend: net new ARR ÷ prior quarter S&M spend.
Stripe Fee Calculator (UK)
Calculate Stripe processing fees for UK merchants — standard, Stripe Tax, Connect and international card uplift.
Apple App Store Fee Calculator
Estimate App Store commission — 30% standard, 15% for small developers (< $1M/year) and subscriptions year 2+.
Google Play Fee Calculator
Google Play's 15% commission on first $1M, 30% above — calculate net revenue from app sales.
AWS Monthly Cost Estimator
Quick estimate of AWS monthly cost — EC2, RDS, S3, CloudFront, data transfer for a UK startup.
UK vs Offshore Dev Rate Calculator
Compare total cost of a UK development team vs offshore — salary, employer NI, management overhead and quality risk adjustment.
SaaS Metrics & Tech Finance 2025/26
UK tech and SaaS businesses in 2025 are increasingly focused on capital efficiency, rule of 40 compliance and sustainable growth metrics following the correction from 2021 valuations. Key benchmarks include monthly churn below 1%, NDR above 100%, CAC payback under 18 months and gross margins above 70%. These calculators give founders, CFOs and finance teams instant access to the numbers that matter for board reporting, fundraising and strategic planning.
Frequently Asked Questions
- What is a healthy monthly churn rate for a SaaS business?
- For SMB SaaS, a monthly churn rate of 0.5–2% is considered acceptable, equating to 6–22% annual churn. Enterprise SaaS should target 0.2–0.5% monthly churn. Best-in-class SaaS businesses achieve net negative churn through expansion revenue, meaning existing customers generate more revenue than is lost through churn.
- What ARR multiple do UK SaaS companies typically sell for?
- UK SaaS valuations in 2025 typically range from 3–8× ARR for bootstrapped profitable businesses and 8–15× for high-growth VC-backed companies. Multiples compressed significantly from their 2021 peaks of 30–50× and have stabilised. Key drivers of premium multiples include growth rate above 40% YoY, net dollar retention above 110%, and gross margins above 75%.
- What are Stripe's fees for UK merchants in 2025?
- Stripe's standard processing fees for UK merchants in 2025 are: 1.5% + 20p for UK consumer cards; 2.5% + 20p for EEA cards; 3.25% + 20p for international (non-EEA) cards. Stripe Tax adds 0.5% per transaction. BACS Direct Debit costs 1% capped at £2, and SEPA Direct Debit costs 0.8% capped at £5.
- How much does AWS cost for a small UK SaaS startup?
- A basic production setup for a UK SaaS startup — 2 app servers (t3.medium), 1 database (db.t3.medium RDS), 100GB S3 storage — typically costs £80–200 per month on AWS. Reserved instances can reduce this by 30–40%. Cost grows significantly with data transfer, higher-tier instances and additional managed services.