Free tools
Everything you need to sanity-check the numbers
Calculators and generators that run in your browser. No account, nothing uploaded. When you want the number explained, not just computed, Duct reads your tools and answers.
- No signup
- Runs in your browser
- Built by the Duct team
SaaS metrics & revenue
Benchmark health and model growth with the numbers finance will ask for.
SaaS Metrics Benchmark Calculator
Churn, LTV:CAC, payback and trial-to-paid, scored against industry medians.
Open calculator → CalculatorCAC / LTV Calculator
Unit economics in one view: CAC, LTV, ratio, and payback with benchmark context.
Open calculator → CalculatorMRR Growth Rate Calculator
Net MRR growth, CMGR, and the rate you need to hit a target.
Open calculator →Paid media efficiency
Planning, pacing or the post-mortem: CTR, CPM, CPC, CPA, ROAS and ROI without a spreadsheet.
CTR Calculator
Click-through rate, projected clicks, and the CTR you need to hit volume goals.
Open calculator → CalculatorCPM Calculator
Cost per thousand impressions, spend scenarios, and efficiency targets.
Open calculator → CalculatorCPC Calculator
Cost per click and what spend looks like at your target CPC.
Open calculator → CalculatorCPA Calculator
Cost per acquisition, conversion scenarios, and budget-safe CPAs.
Open calculator → CalculatorROAS Calculator
Return on ad spend as a revenue multiple, target ROAS gaps, and margin-aware contribution ROAS.
Open calculator → CalculatorMarketing ROI Calculator
ROI, profit, and revenue scenarios for campaign decisions in minutes.
Open calculator →Tracking, social & reporting
Clean campaign links, a brief template your team will fill in, and engagement rates you can compare across posts.
UTM Builder
GA4-friendly campaign links with live preview and validation.
Build UTMs → TemplateWeekly Marketing Brief Generator
A weekly report structure for your role and your stack, one slot per tool.
Generate template → CalculatorEngagement Rate Calculator
Engagement by followers, reach or impressions, comparable across posts.
Open calculator →FAQ
About these tools
Do I need an account?
No. Every tool on this page runs in your browser. The Duct app is a separate download, free with your own keys, and these stay free either way.
How is this related to Duct the product?
Same team. A tool answers one question with the numbers you type in. Duct answers it with the numbers in your tools, every time you ask, and proposes what to change.
Will you store my inputs?
No. The maths runs in your browser and nothing you type leaves it.