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 51 car 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 full history check. £9.95 a report, or £5.96 in trade packs of 25.
Most spec checks show what a model could have been built with. That is the brochure, not the car.
FactorySpecs reads the build record for the individual car from its registration. You see the options that specific car left the factory with and, where the manufacturer records it, what each one cost new: £1,615 for the air suspension pack, £1,230 for the electrically deployable tow bar, £895 for the paint.
Alongside the fitted list you get the model's full option book: every option the factory offered on that trim, with prices. Between the two you can answer the questions that matter. Does it have the pack the advert claims? What did the first owner spend? Is the price fair against a car without those extras?
A seller's advert is only as accurate as the seller. Check the spec before you travel, and know what you are paying for.
See which makes we cover →A history check tells you whether a car is stolen, written off or on finance. Useful, and we sell one. It says nothing about what is fitted.
A spec checker tells you what a model could have. That is the brochure, not the car.
FactorySpecs is the third thing: the factory build of the individual car, option by option, with the price of each. Nobody sells the car you are looking at by the model it belongs to. Don't buy it that way.
Dealers and traders get the same report from £5.96 a car, run from a plate in seconds.
Check the spec before you bid, before the car lands, and before you write the advert. Know that the M Sport Pro pack is really there. Price the part exchange on what's fitted, not what the customer says. Put the priced option list in your listing and let the buyer see it for themselves.
Trade accounts run on a monthly plan: 15 reports for £99 for the smaller forecourt, or 25 for £149. Everything sits in one place: every search you have run, your stock in one list, and reports that land in your inbox and your portal the moment they are ready. You get a direct line to us for anything that needs a second look, first access to new features as we ship them, and a lower price per car as your volume grows.
Open a trade account →Enter a UK registration or VIN and see exactly what’s fitted.
Check a car →