import { Unit } from 'humanize-duration';
type DurationOptions = {
    style?: "long" | "short";
    maxDecimalPoints?: number;
    units?: Unit[];
};
export declare function formatDuration(start?: Date | null, end?: Date | null, options?: DurationOptions): string;
export declare function nanosecondsToMilliseconds(nanoseconds: number): number;
export declare function millisecondsToNanoseconds(milliseconds: number): number;
export declare function formatDurationNanoseconds(nanoseconds: number, options?: DurationOptions): string;
export declare function formatDurationMilliseconds(milliseconds: number, options?: DurationOptions): string;
export declare function formatDurationInDays(milliseconds: number): string;
export {};
