ZeroedTools is a free browser toolbox for FPS players — 12 tools, no download, no login: ⌖ Cross-game sensitivity converter (same cm/360) ⌖ Controller tester — stick drift % + per-game deadzone ⌖ Refresh-rate test — is your "144Hz" really 144? ⌖ Mouse switch-chatter / double-click detector ⌖ Footstep audio trainer + colorblind enemy-color studio ⌖ Aim trainer, reaction, keyboard, monitor & FPS tests Every test ends in a shareable verdict card. No signup, no ads.