Canon RF-S 18-45mm f/4.5-6.3 IS STM 18-45mm

The stabilization is excellent, ranking in the 93rd percentile, but the f/4.5-6.3 aperture is one of the worst we've seen, landing in the bottom 5th percentile. It's a fantastic kit lens that's sharp enough in the center and weighs next to nothing at 130g. Just don't buy it separately unless you find a screaming deal under $100.

Sharpness is a mixed bag. The optical score sits right at the 55th percentile, which translates to 'fine, not fantastic.' In the center, it's crisp enough for the 24MP sensors on most Canon APS-C bodies, but the corners get soft, especially at the wide end. The two aspherical elements and one ED element do some heavy lifting to keep chromatic aberration in check, but don't expect prime-level clarity. Autofocus is where this lens quietly shines. The STM motor is fast, silent, and accurate, placing it in the 86th percentile. It's a genuine pleasure for video work, with none of the hunting or whirring you'd get from older kit lenses. The stabilization is the real hero here, giving you about 4 stops of leeway. In practice, that means you can handhold shots at 1/8th of a second and still get a keeper, which almost makes up for the dim aperture. Almost.

Stacked against the competition, the 18-45mm's weaknesses are glaring. The Viltrox AF 56mm f/1.7 is a prime that runs circles around it for portraits, with an aperture that actually lets you blur a background. The Nikon Z 28mm f/2.8 is similarly compact but a full stop faster, making it a better low-light companion. Even the Tamron 28-75mm f/2.8, while bigger and pricier, offers a constant fast aperture that transforms what you can shoot indoors. The Canon's only real win is size and stabilization. If you value portability above all else, it's hard to beat. But if you care about image quality or shooting in anything but daylight, every competitor here offers a more compelling package.

Value is the real sticking point here. As part of a camera kit, this lens is a no-brainer. It's essentially a freebie that gets you shooting immediately. But if you're looking at buying it separately, the math falls apart fast. We've seen prices ranging from $96 to an absurd $7689 across vendors, which tells you the market for this lens is completely unhinged. At the low end, a renewed copy for under $100 is a steal. At anything over $200, you're getting fleeced. The sweet spot for this lens is inside a cardboard box with a new camera body, not on a shelf by itself.

The Canon RF-S 18-45mm f/4.5-6.3 IS STM is a lens that makes a lot of sense as a kit throw-in and almost none when you're looking at the price tag on its own. It's tiny, weighing just 130g, and the retractable design means it disappears into a bag. The 4-stop stabilization is a standout feature, landing in the 93rd percentile of lenses we've tracked, which helps rescue those dimly lit shots where the slow aperture would otherwise punish you. But that aperture is the elephant in the room. At f/4.5-6.3, it's one of the darkest zooms on the market, sitting in the bottom 5th percentile. You'll feel that limitation every time the sun dips behind a cloud.

Portrait shooters and anyone who shoots indoors without a flash should look elsewhere. The aperture is a real letdown, sitting in the bottom 5th percentile, and the bokeh is nearly non-existent. If you're buying this lens separately for more than $150, you're overpaying for what is fundamentally a kit lens. The optical performance is middle of the pack at best, and the lack of weather sealing means it's not a great choice for outdoor adventurers. If you need a compact zoom for an R10 or R7, try to find one used or refurbished for cheap, or save up for a faster alternative.

The Canon RF-S 18-45mm is a lens defined by its compromises. It's a marvel of miniaturization with genuinely impressive stabilization and autofocus, but the slow aperture hamstrings it in any challenging light. The user sentiment score of 45/100 reflects this split personality. Owners who got it in a kit are mostly happy, praising the crisp center sharpness and versatility. Those who paid separately often feel burned. If you find it for under $100, it's a handy little zoom to keep in the bag. If you're paying retail, skip it and put that money toward a fast prime.