All Tools (175)

Simplify ratios and solve proportions with a missing value.

Calculate RC filter cutoff frequency or solve R or C.

Calculate RC time constant, settling time, cutoff frequency, and charge/discharge progress.

Calculate capacitor or inductor reactance at an AC frequency.

Test JavaScript regex patterns and inspect matches and capture groups.

Decode 4-band and 5-band resistor color codes.

Solve Reynolds number and its fluid-flow variables.

Calculate RL filter cutoff frequency or solve R or L.

Calculate series RLC resonance, Q, bandwidth, impedance, and damping.

Convert RMS, peak, and peak-to-peak waveform values or find RMS from samples.

Check robots.txt rules for a crawler and path.

Calculate ROI, net return, cost basis, and optional annualized return.

Convert numbers to Roman numerals or Roman numerals back to numbers.

Solve K = ½Iω² for rotational energy, inertia, or angular speed.

Find running pace per km or mile from distance and time.

Convert annual salary to hourly and other gross pay equivalents.

Find sales tax, final price, pre-tax price, or tax rate.

Estimate the monthly contribution needed to reach a savings target.

Scientific math functions with degree and radian modes.

Compare SemVer versions and inspect prerelease precedence.

Combine resistors in series or parallel and calculate total current and power.

Solve pendulum period, frequency, length, or gravity.

Estimate conductor skin depth from frequency and material properties.

Create URL-safe slugs and check duplicate page paths.