Gratis online tools

Look up geolocation, ISP, ASN, reverse DNS, and IP format details for any public IPv4 or IPv6 address.

Free multiple choice quiz practice tool — paste questions or use a sample quiz. One question at a time, score at the end, review mistakes.

Parse user agent strings to identify browser, engine, operating system, device type, and bot detection.

Calculate bolt tightening torque, clamp preload, and nut factor K. Modes: torque from preload (T = KDF), preload from torque, recommended torque from proof load and bolt grade, and nut-factor solver. Metric (mm, kN, N·m) and imperial (in, lbf, lbf·ft) with M6–M24 and Grade 5/8 presets. Free, browser-based.

Solve ax² + bx + c = 0 with the quadratic formula. Get roots, discriminant, vertex, and step-by-step work.

Free Telegram chat generator — build realistic Telegram conversation mockups with ticks, replies, and themes. Save locally and export PNG.

Convert amounts between world currencies using live mid-market exchange rates.

Count significant figures, round to N sig figs, and add, subtract, multiply, or divide with correct precision rules. Enter decimals, trailing zeros, or scientific notation. Free, instant, browser-based.

Calculate soil bulk density, moisture content, porosity, and void ratio from sample mass and volume. Supports metric (g, cm³) and imperial (lb, ft³). Free, browser-based.

Convert text between uppercase, lowercase, title case, camelCase, snake_case, and more.

Build Unix cron schedules with presets, custom fields, validation, and plain-English explanations.

Free iMessage generator — build realistic iPhone Messages mockups with blue bubbles, tapbacks, and PNG export. Saved locally in your browser.