A cable lock can be cut in three seconds with a pair of hand-held cutters. A cheap U-lock gives an angle grinder about 60 seconds of resistance. A Sold Secure Diamond-rated lock? Seven minutes or more — long enough that most thieves move on to an easier target.
Your lock is the single biggest factor in bike theft prevention. But with dozens of options ranging from EUR 15 to EUR 300, choosing the right one isn't obvious. Here's what actually matters.
Lock types: what works and what doesn't
U-locks (D-locks) offer the best security-to-weight ratio. A hardened steel shackle of 13mm or thicker resists bolt cutters entirely and forces a thief to use an angle grinder — a loud, conspicuous tool that draws attention. The trade-off is limited reach. U-locks work best when you can wrap them tightly around your frame, a wheel, and a solid anchor point.
Chain locks are the most flexible option. A 10mm+ hardened chain can wrap around wide posts, bike racks, or even two bikes at once. The downside is weight — a Gold-rated chain lock easily weighs 2 to 4 kg. If you park in the same spot daily, keeping a chain locked to your rack makes more sense than carrying it.
Folding locks split the difference. They're compact when folded, reasonably secure, and more flexible than a U-lock. The riveted joints are their weak point, but the best folding locks now carry Sold Secure Gold ratings. Good for commuters who need something portable.
Cable locks are not real security. They exist only as a secondary lock — thread one through your front wheel while your U-lock secures the frame and rear wheel. Never use a cable lock as your only line of defense.
Smart locks add GPS tracking and phone alerts, which sounds great in theory. But their physical security often lags behind traditional locks at the same price point. If you want tracking, a hidden GPS tracker paired with a strong mechanical lock is a better strategy.
Our picks for 2026
Best overall: Kryptonite New York Standard — 16mm hardened steel shackle, Sold Secure Gold rated, around EUR 100-130. It's heavy at 1.8 kg, but that weight is hardened steel standing between a thief and your bike. The double-deadlock mechanism resists prying, and the disc-style cylinder is pick-resistant.
Best for e-bikes: Hiplok D1000 — Sold Secure Diamond rated, around EUR 250-300. If your e-bike cost EUR 3,000+, spending 10% of that on a lock that resists angle grinders for 7+ minutes is a rational investment. The D1000 uses a proprietary material that chews through cutting discs.
Best value: Abus Granit X-Plus 540 — 13mm parabolic shackle, Sold Secure Gold, around EUR 80-100. Lighter than the Kryptonite at 1.4 kg with near-equivalent security. A strong choice for daily commuters who need Gold-level protection without the bulk.
Best portable: Seatylock Foldylock Forever — Sold Secure Gold rated folding lock, around EUR 90-120. 90cm reach when unfolded, 9.5mm hardened steel bars. Folds compactly for backpack or frame mounting.
Best budget: Kryptonite Evolution Mini-7 — Sold Secure Silver, around EUR 50-65. A compact U-lock that's enough for quick stops in lower-risk areas. Not recommended as your only lock for overnight parking.
Understanding security ratings
Two rating systems dominate the market:
Sold Secure (UK-based, globally recognized) tests locks against specific tools for minimum time thresholds:
Bronze — resists basic tools for at least 1 minute
Silver — resists a wider tool set with more sustained attack
Gold — high security for urban environments and valuable bikes
Diamond — the highest tier, tested against specialist tools including angle grinders
ART (Netherlands-based) uses a 1-5 star system and is widely recognized across Scandinavia and Northern Europe. Many Nordic insurance companies require ART 3+ or Sold Secure Gold as a condition for bicycle theft coverage — worth checking your policy before buying a lock.
Our minimum recommendation: Sold Secure Gold for any bike you leave unattended in a city. Diamond for e-bikes or bikes worth over EUR 2,000.
How much should you spend?
A reasonable rule: spend 10-15% of your bike's value on security. A EUR 500 city bike deserves at least a EUR 50-75 lock. An EUR 3,000 e-bike justifies EUR 200-300 on a Diamond-rated lock plus a secondary chain.
That math makes more sense when you consider the alternative. In Sweden, roughly 55,000 bikes are reported stolen each year — making bike theft one of the most common property crimes in the Nordics. In Finland, the number is around 14,000. Recovery rates without bike registration hover at 2-5%. The cost of a good lock is a fraction of the cost of replacing your bike.
A lock is only half the equation
Even the best lock can be defeated given enough time and the right tools. What a lock does is buy time — minutes of loud, visible cutting that most thieves won't risk in a public space.
But time alone doesn't get your bike back if it does get stolen. That's where a stolen bike registry fills the gap. When your bike is in the Bike Registry database with its bicycle serial number, photos, and details, anyone who encounters it — police, bike shops, potential buyers — can check whether it's been flagged as stolen. Research shows that registered bikes have recovery rates around 23%, compared to about 5% for unregistered ones.
A QR sticker on your frame adds a visible signal that your bike is registered and traceable. For a thief calculating risk versus reward, that sticker changes the math.
Lock your bike well. But also register it for free at Bike-Registry.com — because the best security is a lock that buys time and a registry that removes the payoff.
Ready to protect your bike? Download the app and register your bike for free.
