JavaScript Execution Time

How to Measure JavaScript Execution Time - DEV Community

If measuring in Node, process.hrtime.bigint() returns accuracy in nanoseconds.

Standard timers return number of milliseconds from 1970-01-01T00:00:00

// DATE TIMER

const start = Date.now();

await functionToBeMeasured();

const end = Date.now();

console.log(`Execution time: ${end - start} ms`);

// CONSOLE TIMER

console.time('Execution Time');

await functionToBeMeasured();

console.timeEnd('Execution Time');

// PERFORMANCE. TIMER

const start = performance.now();

await functionToBeMeasured();

const end = performance.now();

console.log(`Execution time: ${end - start} ms`);