About CompareMOTHistory

Our Mission

Help UK used car buyers make confident decisions with data-backed MOT insights. No guesswork. No scare tactics. Just reproducible analysis from real DVSA data.

What We Do

We analyze anonymized UK MOT test records to reveal patterns that matter:

  • Pass rates by make, model, age, and fuel type
  • Mileage benchmarks specific to vehicle cohorts
  • Retest patterns and failure-to-pass timelines
  • Regional variations in MOT performance

Why This Matters

The MOT system is the UK's largest vehicle reliability dataset. But raw MOT history for one car doesn't tell you if that car is typical or exceptional for its cohort.

That's where we come in: contextual benchmarks so you can evaluate any vehicle against its peers.

Our Data Source

All analysis derives from the DVSA (Driver and Vehicle Standards Agency) anonymized MOT test dataset covering the 2024 calendar year.

What's included:

  • Test date, result (pass/fail), mileage
  • Vehicle make, model, fuel type, first registration date
  • Postcode area (geographic signal)
  • Test type (normal, retest)

What's NOT included (intentionally excluded by DVSA):

  • VRM/registration numbers
  • Specific defect reasons or advisories
  • Owner information
  • Exact locations

Integrity: We never invent numbers. Every statistic is reproducible from documented code.

Our Methods

  1. Ingest: Stream CSV files into memory-efficient Polars DataFrames
  2. Clean: Normalize make/model names, parse dates, remove duplicates
  3. Features: Calculate vehicle age, detect retests (≤14 days same vehicle)
  4. Analyze: Compute pass rates, mileage bands, retest latency by cohort
  5. Visualize: Generate charts with alt text and methodology notes
  6. Publish: Render content via Jinja2 templates with proper citations

Reproducibility: Full analysis code available in our GitHub repository.

Editorial Standards

Truth > Clicks

We never:

  • Invent statistics
  • Cherry-pick data to support a narrative
  • Use scare tactics to drive conversions
  • Guess at defect reasons when data doesn't support it

We always:

  • State uncertainty and scope limits
  • Provide cohort context (sample sizes, confidence)
  • Link to methodology for every claim
  • Update content when new data arrives

Writing Philosophy (Dean × Gotch)

  • Evergreen content: Fewer, definitive guides refreshed quarterly
  • Scannability: Short paragraphs, bullet lists, clear headers
  • Actionability: Every post includes decision frameworks
  • Accessibility: Plain language, no jargon without definitions

About MOT Ninja

CompareMOTHistory is the content hub. MOT Ninja is the tool:

  • Free: Complete MOT history for any UK vehicle
  • Premium (£9.49): Finance checks, write-off status, stolen vehicle alerts

Two sites, one mission: help you buy used cars with confidence.

Team

We're a small team of data engineers and automotive journalists who got tired of anecdotal "advice" and wanted to bring rigorous analysis to the used car market.

Contact

Questions about the data? Email: [email protected]
Editorial enquiries? Email: [email protected]
Press/media? Email: [email protected]

Found an error? We take accuracy seriously. Please report any issues to [email protected] with:

  • URL of the page
  • Specific claim in question
  • Why you believe it's incorrect

We'll investigate and update within 48 hours.

Data Ethics

  • Privacy: We only use anonymized aggregates. No PII ever appears in public outputs.
  • Transparency: Methodology documented for every statistic.
  • Accountability: Clear correction process; we own our mistakes.

Stay Updated

  • Newsletter: Weekly insights (no spam, unsubscribe anytime)
  • LinkedIn: Latest guides and data drops
  • YouTube: Video deep-dives on MOT patterns

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Last updated: October 2025 | View our privacy policy | Terms of use