Generating a strong WiFi password is the easy part. Where that password actually goes, and what else on the router is worth checking while you're in there, is where most people get stuck, because every brand hides its settings in a slightly different place.
Finding the password field on your router
On TP-Link routers, open a browser and go to tplinkwifi.net or 192.168.0.1, log in with the admin credentials printed on the router unless you've changed them, then go to Wireless → Wireless Settings. You'll see separate fields for the 2.4GHz and 5GHz networks; most people set both to the same password, but you can keep them different if you want to split older and newer devices onto separate bands.
On Netgear routers, the login page is usually routerlogin.net or 192.168.1.1. Once you're in, look under Wireless in the Basic tab. Netgear labels the password field "Password (Network Key)," and like TP-Link it separates the 2.4GHz and 5GHz bands if your router broadcasts both.
On ASUS routers, go to router.asus.com or the router's IP address, then General → Network Map, and click directly on the WiFi icon in the middle of the page, which opens the wireless settings without digging through a menu tree. ASUS also shows the security protocol (WPA2-Personal, WPA3-Personal, or a mixed mode) right next to the password field, worth a glance while you're there.
On Linksys routers, the app has mostly replaced the web login for newer models, but the browser route is still 192.168.1.1, then Wireless settings from the main menu. Mesh systems like Google Nest WiFi, Amazon eero, or Netgear Orbi are managed entirely through their phone apps rather than a browser; look for "WiFi settings" or "Network settings" inside the app, and note that changing the password there updates it across every mesh point in the house at once, not just the main unit. If your router came from your internet provider rather than one you bought separately, common with plans from Comcast/Xfinity, Spectrum, BT and similar, the login page and menu layout will follow the provider's own app or portal instead of the manufacturer's, and searching "[your provider] change WiFi password" gets you there faster than guessing through menus.
WPA2, WPA3, and why the label next to your password matters
A strong password on a weak protocol is still a weak network. WEP, the encryption standard from the early 2000s, can be broken in minutes regardless of how the password looks, and if your router still offers it as an option, that alone is a reason to check its age. WPA2 has been the reasonable baseline for over a decade and remains fine for most homes. WPA3, where it's available, closes several of WPA2's long-standing weaknesses, in particular making offline password-guessing attacks far harder even if someone captures your network's handshake. If your router lists a WPA2/WPA3 mixed mode, that's a sensible middle ground when some of your older devices don't support WPA3 on their own.
The network name is worth a moment too
The SSID, the name your network broadcasts, doesn't affect your password's strength, but it's still worth picking with a little care. Avoid your name, apartment number, or anything else that identifies you or the household to someone standing outside. "Hiding" the SSID so it doesn't appear in the WiFi list is a common suggestion that does very little in practice; the network is still detectable with basic tools, and hiding it mainly makes reconnecting your own devices more annoying. A neutral, forgettable name does more for you than a hidden one.
2.4GHz or 5GHz, and does it matter which
Most routers still broadcast both bands. 2.4GHz reaches further through walls but is slower and more crowded, since it's shared with cordless phones, baby monitors, and older smart-home gear. 5GHz is faster and cleaner but doesn't travel as far. If your router lets you set the same password for both, most devices will pick the better one automatically. If you've split them into two separate networks, put older, low-bandwidth devices like smart plugs and cameras on 2.4GHz and keep laptops and phones on 5GHz where reception allows it.
The admin login is a separate password
It's easy to conflate two different passwords on the same page: the WiFi password that lets a device join your network, and the router's admin password that controls its settings. Changing one doesn't change the other. Default admin logins for most router models are publicly documented, since manufacturers reuse the same default across thousands of units, so leaving it unchanged gives anyone who joins your network, intentionally or not, a way to reconfigure your router entirely. Change both, and consider using a passphrase for the admin login specifically, since it's one you'll occasionally need to type by hand. For a router's WPS PIN setup, note that WPS PINs are only 8 digits and can be brute-forced in hours with freely available tools; turning WPS off entirely is safer than trusting any PIN there, including ones from our own PIN generator, which is built for locks and keypads rather than WPS.
A guest network is worth the five minutes
Most routers offer a guest network as its own toggle, usually near the main WiFi settings, and it's worth turning on even if you rarely have visitors. It keeps anything you don't fully trust, smart bulbs, a friend's phone, a set-top box you bought secondhand, off the same network as your computers and personal files. If a guest device turns out to be compromised, it's isolated from everything that actually matters. Sharing the guest password is also easier without reading it aloud character by character: the WiFi QR code generator turns any password into a code a phone camera can scan directly.
One more thing worth checking while you're logged in
Router firmware updates rarely announce themselves, and a lot of people never open the update tab their router provides after the first setup. Most modern routers can check for updates from the same settings page where the WiFi password lives, and applying them closes security holes that don't get fixed any other way. It's a five-minute task worth doing at the same time you change the password.
Generating the password itself
The generator above builds a password from your browser's secure random source, the same one used for real cryptographic work, and nothing about it touches a server. Length matters more here than almost anywhere else, since router firmware supports up to 63 characters and you'll rarely type this one by hand, so there's little reason to keep it short. For the reasoning behind that, see what makes a password strong, or use the main password generator for anything else you need to secure, from an email account to a social media login. If a site or device asks for an exact length, the 12 and 15 character generator has presets for that, and the random string generator is there for tokens and keys that aren't passwords at all.