Time utilities. Provides cross-platform high-resolution timing and measurement helpers.
19 declarations
<T>(fn: () => Promise<T>, timer?: Timer): Promise<{ result: T; timing: TimeResult; }> Time an asynchronous function execution.
fn- Async function to time
() => Promise<T>timer- Timer to use (defaults to timer_default)
timer_defaultPromise<{ result: T; timing: TimeResult; }> Object containing the function result and timing information
(ns: number, unit: TimeUnit, decimals?: number): string Format time with a specific unit.
ns- Time in nanoseconds
numberunit- Unit to use ('ns', 'us', 'ms', 's')
decimals- Number of decimal places (default: 2)
number2string Formatted string like "3.87μs"
(ns: number, decimals?: number): string Format time with adaptive units (ns/μs/ms/s) based on magnitude.
ns- Time in nanoseconds
numberdecimals- Number of decimal places (default: 2)
number2string Formatted string like "3.87μs" or "1.23ms"
(fn: () => unknown, iterations: number, timer?: Timer): Promise<number[]> Measure multiple executions of a function and return all timings.
fn- Function to measure (sync or async)
() => unknowniterations- Number of times to execute
numbertimer- Timer to use (defaults to timer_default)
timer_defaultPromise<number[]> Array of elapsed times in nanoseconds
1000000 1000000000 1000 Time units and conversions.
(ns: number): number Convert nanoseconds to milliseconds.
nsnumbernumber (ns: number): number Convert nanoseconds to seconds.
nsnumbernumber (ns: number): number Convert nanoseconds to microseconds.
nsnumbernumber <T>(fn: () => T, timer?: Timer): { result: T; timing: TimeResult; } Time a synchronous function execution.
fn- Sync function to time
() => Ttimer- Timer to use (defaults to timer_default)
timer_default{ result: T; timing: TimeResult; } Object containing the function result and timing information
(values_ns: number[]): TimeUnit Detect the best time unit for a set of nanosecond values. Chooses the unit where most values fall in the range 1-9999.
values_ns- Array of times in nanoseconds
number[]TimeUnit Best unit to use for all values
Record<TimeUnit, string> Display labels for time units (uses proper Unicode μ for microseconds).
Timer Timer interface for measuring elapsed time. Returns time in nanoseconds for maximum precision.
nowGet current time in nanoseconds
() => numberTimer Browser high-resolution timer using performance.now(). Converts milliseconds to nanoseconds for consistent API.
Precision varies by browser due to Spectre/Meltdown mitigations: - Chrome: ~100μs (coarsened) - Firefox: ~1ms (rounded) - Safari: ~100μs - Node.js: ~1μs
For nanosecond-precision benchmarks, use Node.js with timer_node.
Timer Auto-detected timer based on environment. Uses process.hrtime in Node.js, performance.now() in browsers. The timer function is detected once and cached for performance.
Timer Node.js high-resolution timer using process.hrtime.bigint(). Provides true nanosecond precision.
TimeResult Result from timing a function execution. All times in nanoseconds for maximum precision.
elapsed_nsElapsed time in nanoseconds
numberelapsed_usElapsed time in microseconds (convenience)
numberelapsed_msElapsed time in milliseconds (convenience)
numberstarted_at_nsStart time in nanoseconds (from timer.now())
numberended_at_nsEnd time in nanoseconds (from timer.now())
numberTimeUnit Time unit for formatting.