A complete guide to finding out what optional extras are on any UK car.
When buying a used car, the advert might say “fully loaded” or “high spec” — but what does that actually mean? Factory-fitted options vary enormously between individual cars of the same model. Two identical-looking BMWs, Jaguars, or Audis can differ by thousands of pounds in original specification.
This guide explains the different methods for checking what factory options are fitted to a car, and which method gives you the most accurate results.
The VIN (Vehicle Identification Number) is a unique 17-character code assigned to every vehicle at manufacture. It encodes information about the factory build, including which optional extras were fitted. A VIN decoder or car spec lookup by VIN can reveal the complete factory build sheet.
You can find the VIN on the V5C registration document, on the driver’s door frame, at the base of the windscreen, or in the vehicle’s infotainment system.
If you have the UK registration, you can check a car’s spec by reg without needing to find the VIN yourself. Services like FactorySpecs resolve the registration to a VIN automatically, then decode the factory specification. This is the quickest way to do a vehicle spec check or car spec check for any UK-registered vehicle.
Some manufacturer dealers can look up the original specification if you provide the VIN. However, this usually requires visiting or calling a dealership, may take days, and the information is often provided verbally rather than in a structured report.
Sites like Auto Trader and manufacturer websites show what’s standard on a particular model. This tells you the base specification, but not which optional extras were added to this specific car. It’s model-level guesswork, not VIN-level data.
When you check a car’s spec through VIN decoding, you get far more than just a list of features. A comprehensive vehicle spec check includes:
Factory-fitted options — every extra ordered when the car was new, with original retail prices where available. This includes individual options, option packs, paint, trim, wheels, and technology packages.
Standard vs optional — the distinction between what comes as standard on that model and what was a paid extra. This is critical for understanding the true spec level.
Option values — what those extras cost when the car was new. A car with £8,000 in factory options is genuinely different from one with £800, even if the model badge is the same.
Different manufacturers encode factory options differently, which is why a specialist decoder is more accurate than a generic lookup.
Checking BMW spec by reg is one of the most common searches because BMW buyers care deeply about specification — the difference between a base SE and an M Sport with Technology Pack and Comfort Package is significant in both desirability and value.
A common misconception is that an HPI check or vehicle history check will tell you what’s fitted to a car. It won’t. HPI checks focus on finance agreements, theft records, write-off status, and mileage discrepancies. They’re important, but they don’t tell you anything about factory-fitted extras.
Verify the seller’s claims. The advert says “fully loaded” — but is it? A spec check tells you exactly what was fitted at the factory.
Negotiate from strength. If you can see the car has £2,000 in factory options instead of the £8,000 the seller implies, you have real data to support a lower offer.
Compare like for like. When choosing between two similar cars, the one with genuine factory options will hold its value better.
Spot missing features. If the spec check shows factory navigation but the car has an aftermarket head unit, that’s worth knowing.
Factory options are just as important for EVs. Battery and charging specifications vary significantly. A spec check for electric vehicles like the Jaguar I-PACE, BMW iX, Tesla Model 3, or Volkswagen ID.4 reveals not just the optional extras but also battery capacity, charging specifications, WLTP range, and warranty status.
FactorySpecs is the UK’s first tool specifically built to check factory-fitted options for retail car buyers. Enter any UK registration or VIN and the system decodes it against manufacturer build records across 39 brands.
Every lookup starts with a free MOT and tax check powered by DVLA and DVSA data. The full report adds factory-fitted options with original prices, live market valuations, performance data, and a comprehensive HPI check.
Enter a UK registration or VIN and see exactly what’s fitted.
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