A workbench for marketing and AI.
Free, ungated tools designed for understanding. Each one runs entirely in your browser, requires no signup, and documents its method, assumptions, and limitations.
ROAS calculator
Free ROAS calculator: divide revenue by ad spend, find your break-even ROAS from gross margin, and see profit on ad spend. No signup, runs in your browser.
CPM, CPC, CTR & CPA calculator
Free calculator for CPM, CPC, CTR, CVR, CPA and frequency from spend, impressions, clicks and conversions. No signup, nothing you enter leaves your browser.
Cost per lead (CPL) calculator
Free cost per lead calculator: get CPL from spend and leads, plus CAC, projected revenue and ROI from close rate and deal value. No signup required.
Ad budget pacing calculator
Free ad budget pacing calculator: compare actual spend to ideal spend to date, project end-of-period spend, and get a daily target. No signup, no tracking.
Incrementality & lift calculator
Free incrementality calculator: enter test and holdout conversion rates to get lift, incremental conversions and iROAS. No signup, runs in your browser.
SERP snippet preview
Preview how your page title and meta description appear in Google search results. Free pixel-width checker for desktop and mobile snippets — runs entirely in your browser.
Robots.txt tester
Test robots.txt rules against any URL path and user-agent. Free RFC 9309 tester runs fully in your browser with no signup and nothing uploaded to a server.
Schema markup generator (JSON-LD)
Generate valid JSON-LD schema markup for Article, FAQ, HowTo, Product and more. Free structured data generator — no signup, copy-paste ready output.
Hreflang tag generator
Build reciprocal hreflang link tags for every language and region version of a page, with x-default. Free generator, no signup, runs in your browser.
llms.txt generator
Create a spec-compliant llms.txt file for your site with sections, links and descriptions. Free markdown generator — no signup, nothing stored.
Character counter
Free character counter that checks your text against Google Ads, meta tag, and social limits live. Counts characters, words, and reading time — nothing you type is stored.
Word counter
Free word counter with characters, sentences, paragraphs, and reading time. Built for content and SEO writing — runs entirely in your browser, nothing stored.
Keyword density checker
Free keyword density checker: paste page copy to see the most frequent words and 2- and 3-word phrases with density. Runs in your browser, nothing stored.
XML sitemap generator
Free XML sitemap generator: paste a list of URLs and get a valid sitemap.xml with optional lastmod, changefreq, and priority. Runs in your browser.
Redirect checker
Free redirect checker: trace the full 301/302 redirect chain for any URL and see the final destination and each status code. No signup required.
LLM API cost calculator
Calculate LLM API costs per request, day and month from your own token prices and volumes, with prompt caching discounts. Free, no signup required.
AI agent cost estimator
Estimate AI agent costs across multi-step tasks, including context growth and cache hits. Free calculator — no signup, runs entirely in your browser.
AI automation ROI calculator
Work out payback weeks and first-year ROI for an AI automation from hours saved, build cost and run cost. Free calculator, no signup, no data stored.
LLM token counter & cost estimator
Estimate token counts for any text with two disclosed heuristics, plus cost at your own per-million-token prices. Free, no signup, fully client-side.
A/B test significance calculator
Check whether an A/B test result is statistically significant. Free two-proportion z-test calculator with p-value, confidence interval, and relative lift — runs entirely in your browser.
A/B test sample size calculator
Free A/B test sample size calculator using a two-proportion z-test. Get the sample size per variant and test duration. No signup, runs in your browser.
UTM campaign URL builder
Build campaign tracking URLs with utm_source, utm_medium, and utm_campaign parameters. Free UTM link generator with validation and naming guidance — runs entirely in your browser.
Customer LTV calculator
Free customer LTV calculator using order value, purchase frequency, gross margin and retention years. Includes LTV to CAC ratio and CAC payback. No signup.
Conversion rate calculator
Free conversion rate calculator: get CVR from conversions and visitors, plus revenue and value per visitor. No signup, runs entirely in your browser.
Percentage change calculator
Free percentage change calculator: get the percent increase or decrease between two values, the absolute difference, and the multiplier. Runs in your browser.
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