Tools — CodexHow

Every tool on this site runs entirely in your browser, reads its numbers from the same facts module the reference pages use, and links its result so you can share or bookmark exactly the scenario you priced. None of them call an external API to produce a result.

Start with the cross-provider comparison if you're actually choosing between ecosystems, or the token & cost estimator if you just need a fast answer for a single request. The rest cover subscription-vs-API, context-window planning, model selection, usage tracking, batch economics, rate-limit tiers, and prompt-caching savings — each solving one specific planning question rather than trying to be a single do-everything calculator.

Every result is URL-encoded, so a scenario you've priced is a link you can share or bookmark rather than a screenshot that goes stale the moment a rate changes.