4 free tools
Marketing tools built for real work
Practical campaign, advertising and messaging calculators for growth teams. Every tool is designed to expose its inputs and outputs clearly instead of hiding the logic behind a vague score.
↗UTM Campaign URL BuilderBuild consistent campaign URLs with source, medium, campaign, term and content parameters.→↗Marketing Metrics CalculatorCalculate CTR, CPC, CPM, conversion rate, CPA and ROAS from one input set.→↗ROAS CalculatorCalculate return on ad spend, break-even ROAS and contribution after ad spend.→↗Email Subject Line AnalyzerCheck subject length, word count, capitalization, punctuation and promotional wording.→
Why ToolboxKart Marketing tools?
Fast interfaces, plain-language explanations, mobile-friendly layouts and no unnecessary account wall for the utilities in this release.
Tool first
The working interface appears before long-form SEO content, so you can finish the task quickly.
Transparent logic
Calculators disclose formulas or assumptions where they matter, and analyzers avoid pretending subjective checks are scientific facts.
Reusable results
Copyable output and clean formatting are included where they improve the workflow.