All Tools (175)

Build a DKIM TXT record for email signing.

Build a DMARC TXT record for domain email protection.

Check DNS record values before adding them to a provider.

Calculate PWM timing plus ideal average and RMS voltage.

Calculate point-charge field strength, direction, and test-charge force.

Calculate point-charge electric potential from charge and distance.

Inspect SPF, DKIM, DMARC, and delivery path headers.

Convert J, kJ, MJ, Wh, kWh, cal, kcal, and BTU.

Find the final exam score needed to reach a target course grade.

Solve force, mass, or acceleration with F = ma.

Calculate and simplify arithmetic with two fractions.

Solve friction force, coefficient, or normal force with F = μN.

Estimate fuel needed and fuel cost for a trip from distance and efficiency.

Convert km/L, L/100 km, US mpg, and UK mpg.

Calculate GCD and LCM for two whole numbers.

Calculate term and cumulative GPA on a credit-weighted 4.0 scale.

Solve gravitational potential-energy change, mass, or height.

Generate SHA-2 hashes for text and files locally.

Inspect an HTML heading outline and spot skipped levels.

Solve F = kx and elastic spring energy.

Convert text to and from HTML entities directly in your browser.

Parse and inspect raw HTTP header fields locally.

Find HTTP status meanings and next steps.

Solve liquid pressure, depth, or density with p = ρgh.