Gratis online tools

Tune CSS filter effects like blur, brightness, contrast, and hue-rotate with live preview and copy-ready CSS.

Format and beautify HTML markup with indentation, readable tag breaks, and optional minification.

Calculate gear ratio, output RPM, and torque multiplier for spur gear trains. Single-stage, compound 2-stage, RPM solver, and tooth-count finder for target ratios. Enter driver and driven tooth counts — get speed reduction and ideal torque gain. Free, browser-based.

Combine and propagate measurement uncertainty with root-sum-of-squares (RSS). Add, subtract, multiply, or divide values with ± uncertainties, convert percent uncertainty, and compute expanded uncertainty U = k·u. Free, instant, browser-based.

Calculate percent error, absolute error, relative error, and percent difference between measured and accepted values. Step-by-step formulas for physics and chemistry lab reports. Free, instant, browser-based.

Generate formatted lab notebook entries from your experiment details. Full entries, procedure logs, or formal experiment reports with objective, materials, procedure, observations, results, and conclusions. Copy and paste into your notebook. Free, browser-based.

Split a PDF into separate files by page, fixed chunks, or custom ranges — entirely in your browser.

Create soft neumorphic UI shadows for raised, pressed, and flat surfaces with copy-ready CSS and Tailwind classes.

Encode UTF-8 text to Base64 instantly in your browser with byte-size stats.

Look up mail exchange (MX) DNS records for a domain, sorted by priority with mail host IP resolution.

Find codons in RNA or DNA — search AUG, stop codons, scan reading frames, and view codon frequencies. Free, instant, browser-based.

Add, subtract, multiply, transpose, invert, and find determinants of matrices up to 6×6.