Razer Basilisk V4 Pro adds AI key but crowds thumb controls

Razer has released the Basilisk V4 Pro, a refresh of its gaming mouse line that adds an artificial intelligence key and extends battery life, but the new button layout compromises thumb reach. The update arrives two years after the Basilisk V3 Pro 35K launched in October 2024. Tom's Hardware senior editor Sarah Jacobsson Purewal reviewed the device and described it as a strong all-rounder for players seeking more functionality than a stripped-down shooter mouse, though she noted awkward design changes.

The mouse now includes 12 programmable buttons, up from 10 on the previous model. Two new keys were added: a third thumb button that opens an AI prompt by default, and a profile switch beside the left mouse button. Purewal found the placement of these keys problematic. The profile button sits at the front edge of the 5.02-inch device, making it difficult to press comfortably for users with medium-sized hands and long fingers.

The addition of the AI button has created a more significant ergonomic issue. Because the new key is the same size as the existing thumb buttons, it pushes the other controls back. This leaves the first thumb button, labeled MB4, too far away to reach comfortably. Purewal stated that all three thumb buttons felt slightly off, even after remapping, and questioned whether every peripheral needs a dedicated AI prompt button.

Despite the layout changes, the V4 Pro offers improved hardware specifications. It uses the Focus Pro 50K optical sensor, which reaches 50,000 DPI and 930 IPS, and tracks on most surfaces, including glass at least 4mm thick. The fourth-generation switches are rated for more than 100 million clicks and produced no misclicks or double-clicks during testing. The black version weighs 3.53 ounces (100g), which is almost half an ounce lighter than the V3 Pro 35K at 3.95 ounces (112g).

Battery life has increased from 150 hours to 200 hours at 1,000 Hz polling over 2.4GHz wireless. At the maximum 8,000 Hz polling rate, the battery lasts 54 hours. The device connects via 2.4GHz wireless, Bluetooth, or USB-C. Razer launched the mouse alongside the Mouse Dock V2 Pro, a separate accessory priced at $69.99 that includes an integrated 8,000 Hz receiver and eight RGB zones.

The Basilisk V4 Pro is priced at $169.99 in black and white. The box includes a USB-A dongle, an adapter, and a 6-foot braided cable, but does not include a HyperFlex cable or grip tape. Purewal praised the tilt wheel's precision tactile mode but found the free-spin setting too sensitive. She positioned the mouse between the DeathAdder V4 Pro and the Naga V3 Pro, recommending it for players who want a balance of weight, battery life, and button count.