Bike lock ratings: how to read Sold Secure, ART and FUB levels

On the box of a bike lock you may read ‘level 15’, ‘Sold Secure Gold’ or a logo with two wheels. The three don’t say the same thing, and none of them says how long yours will last against a well-equipped thief. Independent labels do exist: Sold Secure in the UK [1], Stichting ART in the Netherlands [3], the FUB’s anti-theft commission in France [5]. What they have in common is that each rates a lock on a scale of its own. Sold Secure is the home-grown one for British readers, and the other two are worth knowing all the same.

Who tests what: three labels, three scales

Sold Secure, a company based in Rugby, awards four levels: Bronze, Silver, Gold and Diamond. A product is graded by how long it resists specific tools, and each level comes with its own tool list: basic for Bronze, enhanced for Silver, dedicated for Gold, specialist for Diamond [1]. The ratings page gives no durations in minutes: all that is known is that there is one, and that it grows with the level.

The category matters as much as the level. Sold Secure distinguishes ‘Pedal Cycle’ (pedal bikes) from ‘Powered Cycle’ (motorbikes and electric bikes), and the body states that in the second, a Diamond product is tested against the angle grinder while a Gold one is not [1]. In its catalogue, many locks carry two labels at once, for example ‘Powered Gold’ and ‘Pedal Diamond’ [2]. A ‘Gold’ with no category therefore doesn’t tell you much.

In the Netherlands, Stichting ART tests, approves and certifies the locks sold in the country, from D-locks to chains. The logo, with its stars and an approval number, appears on the product [3]. The scale runs from one to five stars: ART-1 for minimal protection, ART-2 for bicycles, ART-3 for mopeds, ART-4 and ART-5 for motorbikes [3]. The tests include hacksaw and bolt-cutter attacks, as well as lock-picking: the more attacks a lock withstands, the more stars it earns [4].

In France, the FUB’s anti-theft commission, which has been testing since 2002 with members of the federation, has put more than 700 locks through their paces [6]. It keeps just two levels, and in 2025 only 30 of the 46 locks tested earned the 2 roues [7]. The ‘1 roue’ (one wheel) level marks a lock that resists for one minute against hand tools shorter than 30 cm that are easy to conceal: it matches the smash-and-grab thefts of the public street. The ‘2 roues’ (two wheels) level demands the same minute against aggressive hand tools that are less discreet, up to 75 cm long, and only this level carries the ‘recommended by the FUB’ wording [5].

Why no equivalence table exists

You will sometimes find tables that line up Gold, ART-3 and 2 roues. None of the three bodies publishes such a correspondence, and for good reason: the protocols differ in tools, durations and the way of counting. The FUB, for example, judges hand tools over one minute [5], whereas Sold Secure speaks of graded tool lists [1] and ART counts attacks repelled [4]. Putting an equals sign between these scales is rather like comparing shoe sizes with glove sizes.

Manufacturers’ own levels pose a sharper problem still. According to Stiftung Warentest, they are neither standardised nor verifiable: one brand offers six levels, another ten, a third fifteen [12]. In the 2023 test, a chain lock rated 5 out of 10 beat another, rated 10 out of 10, which weighs nearly four times as much and costs nearly €150 more [12]. That is not to say the level lies: the ranking also weighs handling. But it shows that a brand’s number says nothing about how two models from different brands compare.

What insurers ask for: the threshold changes with the policy

Use is what gives the labels their weight: the insurer of a stolen bike checks the lock before it pays. Its threshold varies with the company and with the date of purchase, as the three public examples below show.

For a £1,200 bike, Gold or Diamond is now required at Bikmo and at Cycleplan alike [8, 9], whereas Silver was enough at Bikmo before July 2025 [8]. In France, the FUB says that insurers require the 2 roues level [6]. After a theft, insurers also ask for proof: an invoice, a bank statement, the packaging or a photo of the lock at Cycleplan [9], a till receipt and both keys, the one in use and the spare, in the Netherlands [3].

The type of lock matters as much as the level

Testers agree on a ranking by type. According to the FUB, you need at least a D-lock rated 2 roues: it is the best protection against theft. Chains that reach this level are very heavy, folding locks are markedly more vulnerable than D-locks because of their flat arms, ‘boa’ armoured-cable locks resist far less, and cables are tested to show how inadequate they are [6]. The ADFC, on the German side, likewise puts D-locks at the top, with armoured chains and cables almost as secure [10].

The angle grinder is the breaking point: the ADFC writes that quality D-locks can hardly be forced except with one, and that models with a tungsten carbide coating resist it far better but cost several hundred euros [10]. Stiftung Warentest makes it the ‘final boss’ of its tests: its best lock costs €300, but it found break-in-resistant models from €50 and from 800 g [11].

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Which level for which bike and which place

The sources give guidelines, not a grid. For Sold Secure, Bronze targets the opportunist thief, Silver the determined thief in a risk area, Gold the resolute thief in a high-risk setting, and Diamond the most determined thief in a very high-risk setting [1]. The ANWB reserves ART-3 for expensive electric bikes, speed pedelecs and stations or big cities, and judges a second ART-2 lock sufficient in a low-exposure area [4]. The ADFC, for its part, sets a minimum: a lock should hold for at least three minutes against a break-in attempt [10].

My reasoning comes down to three questions. What is the bike worth, and does the insurance contract fix the level? Where does it sleep: a locked cellar or a station hoop? How long does it stay parked? An electric mountain bike left for eight hours outside a workplace calls for a different level from a town bike left for twenty minutes outside a bakery. And the best rating is no use if the lock isn’t put to work.

Locking it properly: the level isn’t everything

• Secure it, don’t just close it: a bike that is merely blocked can be carried off; the frame must pass through the lock, tied to a fixed point [12].
• Keep the lock tight: hold it off the ground and limit the empty space, so the tool and the lever find less room [8].
• Double up: the ADFC recommends two locks of different types, as thieves often specialise in one type [10]; the ANWB finds that only 36% of Dutch cyclists add a second one [4].
• Keep the proof: invoice, photo of the lock and keys, which insurers require [3, 9].
• Mark the bike: a unique number, engraved and registered (BicyCode), helps get it back, and it is compulsory on new bikes sold by a professional [7].

In short: choosing without trusting the number

An independent label (Sold Secure, ART, FUB 2 roues) says that a lock was attacked in a laboratory under a protocol known to the body. That is more reliable than a manufacturer’s level, but it reads on its own scale, never on the neighbour’s. Keep your insurer’s threshold in mind, choose a D-lock of the right level before anything else, double it up in exposed places and always lock the frame. The guide to compulsory cycling equipment covers the rest of the ride.

Worth watching

Global Cycling Network shows how a portable angle grinder changes bike theft, how to lock a bike to deter opportunist thieves, and what the new angle-grinder-resistant locks offer.

The video is hosted by YouTube (Google): nothing loads until you play it, and Google may then set cookies.

Julien de Jurquet

Campervans, motorhomes, cycling and calculators

Julien de Jurquet writes for Outfarer about campervans, motorhomes, cycling and calculators. He reads instruction manuals to the very end and never lets a figure through without its unit, so that your choices rest on sums rather than promises.

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