# Plain Reckoner

> Free business message tools and practical research. Explain an offer, plan a homepage and record reader feedback. Historical publisher research and datasets remain available with dates and limitations.

This is an optional navigation index for compatible tools. Canonical HTML pages are authoritative. This file does not set crawler permissions, grant extra licences or guarantee search or AI inclusion.

## Start here
- [How to use the free tools](https://plainreckoner.com/faq/#how-to-use-the-tools): Step-by-step instructions, matching units, private sharing and CSV imports.
- [FAQ](https://plainreckoner.com/faq/): Static questions and answers about the tools, coverage and privacy.
- [Free tool directory](https://plainreckoner.com/app/): Message and homepage tools, plus website and store calculators. No account required.
- [Offer Builder](https://plainreckoner.com/app/offer/): Enter audience, offer, intended result and action. Editable template drafts; no AI model or conversion prediction.
- [Homepage Planner](https://plainreckoner.com/app/homepage/): Reuse the offer, add genuine proof and process, export a simple HTML outline.
- [Page editor](https://plainreckoner.com/app/editor/): Edit HTML and CSS locally, inspect a script-free sandboxed preview, copy scoped HTML/CSS or AI-builder instructions, download a standalone page or a bounded JSON backup. No automatic publishing or AI request.
- [CTA Lab](https://plainreckoner.com/app/cta/): Compare action wording; optionally calculate recorded rates with explicit denominators.
- [Reader Check](https://plainreckoner.com/app/reader-check/): Save a draft version and record answers from readers you recruit. No supplied participant panel.
- [Test Planner](https://plainreckoner.com/app/test-plan/): Record a hypothesis, outcome, recruitment and review period. No automatic statistical winner.
- [AI handoff instructions](https://plainreckoner.com/faq/#continue-with-ai): Review, redact and copy live tool context to your chosen AI chat. No automatic provider submission or native account connection.
- [Legacy publisher tools](https://plainreckoner.com/app/start/): RPM, listing benchmarks, network checks and public-site inspection.
- [Revenue planning lab](https://plainreckoner.com/app/planning/): Three local scenario tools with formulas, worked examples and explicit limits.
- [Data catalogue](https://plainreckoner.com/data/): Public data samples, external source tables, row definitions, methods and caveats.
- [Research findings](https://plainreckoner.com/notes/): Dated findings and source links.
- [About and authorship](https://plainreckoner.com/about/): What this project measures and how.

- [AdSense report checker](https://plainreckoner.com/app/ad-metrics/): Page RPM, impression RPM, click rates and request coverage from matching report totals. Local calculation; no account access or earnings forecast.
- [Tool index JSON](https://plainreckoner.com/tools.json): Tool URLs, input units, output meanings, privacy and limits. Optional navigation aid, not an endorsement request.

- [Worked calculation checks](https://plainreckoner.com/tool-checks.json): Input, expected result and current result from our own checks. Not an independent audit.

## Published data
- [Public ad-seller directory](https://plainreckoner.com/data/ad-seller-directory/): Checked seller-ID records from networks’ published files, with source hashes and exclusions. Not a site-earnings dataset.
- [What a thousand pageviews earned from ads, by subject, across 123 broker-checked businesses](https://plainreckoner.com/data/rpm-by-niche/): 123 published rows; One measured business: its niche, its RPM, and the months and traffic behind it.
- [Listing multiples by business model across 2,661 sold-status marketplace records](https://plainreckoner.com/data/sale-multiples-by-business-model/): 2661 published rows; One sold-status listing: recorded listing price, reported earnings and listing multiple.
- [Which AI crawlers 1,020 small ad-funded publishers name and block in robots.txt](https://plainreckoner.com/data/ai-crawler-policy-in-robots-txt/): 1020 published rows; One publisher’s robots.txt file: which AI crawlers it names, which it actually blocks, which names it carries that no vendor documents, and whose template it was written from.
- [Where a publisher’s ads.txt and their ad network’s own seller list disagree, across 462 checked relationships](https://plainreckoner.com/data/ads-txt-against-seller-lists/): 462 published rows; One relationship between a publisher and an advertising network: whether both files agree about it, and what the publisher’s own file looked like when it was read.
- [Combined public data JSON](https://plainreckoner.com/data/all-datasets.json): Original public rows and separate calculated views. Different units and potentially overlapping samples; do not add them into a unique-site count.

## Useful explanations
- [AdSense RPM versus CPM](https://plainreckoner.com/notes/adsense-rpm-vs-cpm-explained/): Simple definitions, worked example and primary sources.
- [Good search position, few clicks](https://plainreckoner.com/notes/search-console-good-position-low-clicks/): Why a blended average is not an audience size.
- [Understand analytics before automation](https://plainreckoner.com/notes/understand-website-analytics-before-automating/): Check units, matching dates and decision costs; hypothetical worked example.
- [Traffic up, ad revenue down](https://plainreckoner.com/notes/traffic-up-ad-revenue-down/): A reproducible synthetic example and diagnostic steps, not observed network-performance data.
- [Session RPM versus page RPM](https://plainreckoner.com/notes/session-rpm-vs-page-rpm/): Keep denominators consistent.
- [Listing prices versus sale prices](https://plainreckoner.com/notes/listing-price-vs-sale-price-website-valuations/): Closing prices are not verified.

## Interpretation
Check each page's measurement date, evidence grade, sample and caveats before reuse. Historical, sale-selected observations are not a census or an earnings forecast. The instant question tool retrieves published excerpts and does not generate new evidence. Public data reuse is governed by the licence on each dataset page. Current crawler rules are at https://plainreckoner.com/robots.txt.