# Aback Audit

> Server side website audits for SEO, AI search readiness, structured data, performance, accessibility and security.

Aback Audit reads a public website the way a crawler would and reports what it finds.
It is free, needs no account and no API key, and every audit returns a scored, machine readable report.

## Start here

- [Run an audit](https://abackaudit.com/audit): the web interface.
- [REST api](https://abackaudit.com/docs/index.md): the endpoints, the limits and the error codes.
- [Check catalog](https://abackaudit.com/checks.json): every check with its severity and description.
- [Report schema](https://abackaudit.com/agents/report.schema.json): the shape of a report.
- [Free tools](https://abackaudit.com/tools): single-purpose checkers and generators, such as the robots.txt checker and the llms.txt generator.
- [Guides](https://abackaudit.com/guides): how to fix what the audit finds, from technical SEO to AI search readiness.
- [Monitoring](https://abackaudit.com/monitors): scheduled re-audits with alerts to Slack, Discord, a webhook or email.

## The checks

- [Crawlability](https://abackaudit.com/checks?category=crawl): 10 checks.
- [AI search readiness](https://abackaudit.com/checks?category=ai): 7 checks.
- [On-page SEO](https://abackaudit.com/checks?category=page): 11 checks.
- [Structured data](https://abackaudit.com/checks?category=schema): 5 checks.
- [Performance](https://abackaudit.com/checks?category=perf): 9 checks.
- [Accessibility](https://abackaudit.com/checks?category=a11y): 5 checks.
- [Security headers](https://abackaudit.com/checks?category=sec): 8 checks.

## For agents

- [MCP server](https://abackaudit.com/api/mcp): run audits and read reports over the Model Context Protocol.
- [Server card](https://abackaudit.com/.well-known/mcp/server-card.json).
- [Agent skills](https://abackaudit.com/.well-known/agent-skills/index.json).

## How to score a site

Each check earns 1 point for a pass, 0.5 for a warning and 0 for a fail.
Checks are weighted by severity: critical 5, high 3, medium 2, low 1.
A category score is 100 times the weighted points over the sum of the weights of its scorable checks.
The overall score is the weighted mean of the category scores, using the category weights.
A failing critical check caps the overall score at 59.