Python time Module

import time
 
# Unix timestamp (seconds since epoch)
print(time.time())  # 1711022400.123456
 
# Monotonic clock (for measuring intervals)
print(time.monotonic())  # 123456.789
 
# Performance counter (highest resolution)
print(time.perf_counter())  # 0.123456789

import time
 
print("Starting...")
time.sleep(2.5)  # Sleep for 2.5 seconds
print("Done!")
 
# Sub-second sleep
time.sleep(0.1)  # 100 milliseconds

import time
 
# For general timing
start = time.monotonic()
# ... do work ...
elapsed = time.monotonic() - start
print(f"Took {elapsed:.3f} seconds")
 
# For benchmarking (higher precision)
start = time.perf_counter()
# ... do work ...
elapsed = time.perf_counter() - start
print(f"Took {elapsed:.6f} seconds")

import time
 
# Current local time as struct
local = time.localtime()
print(local.tm_year)   # 2026
print(local.tm_mon)    # 3
print(local.tm_mday)   # 21
print(local.tm_hour)   # 14
print(local.tm_min)    # 30
print(local.tm_wday)   # 4 (Friday, 0=Monday)
print(local.tm_yday)   # 80 (day of year)
 
# UTC time as struct
utc = time.gmtime()
 
# From timestamp
ts = 1711022400
local = time.localtime(ts)
utc = time.gmtime(ts)

import time
 
# Current time formatted
print(time.strftime("%Y-%m-%d %H:%M:%S"))
# 2026-03-21 14:30:00
 
# From struct_time
t = time.localtime()
print(time.strftime("%A, %B %d, %Y", t))
# Friday, March 21, 2026
 
# Common formats
print(time.strftime("%Y-%m-%d"))      # 2026-03-21
print(time.strftime("%H:%M:%S"))      # 14:30:00
print(time.strftime("%I:%M %p"))      # 02:30 PM
print(time.strftime("%Y%m%d_%H%M%S")) # 20260321_143000

import time
 
# Parse string to struct_time
t = time.strptime("2026-03-21 14:30:00", "%Y-%m-%d %H:%M:%S")
print(t.tm_year)  # 2026
print(t.tm_hour)  # 14
 
# Convert to timestamp
ts = time.mktime(t)
print(ts)  # 1711042200.0

import time
 
class Timer:
    def __enter__(self):
        self.start = time.perf_counter()
        return self
    
    def __exit__(self, *args):
        self.elapsed = time.perf_counter() - self.start
        print(f"Elapsed: {self.elapsed:.4f}s")
 
# Usage
with Timer():
    time.sleep(0.5)
# Elapsed: 0.5012s

import time
 
# Wall clock time (includes sleeping/waiting)
wall_start = time.perf_counter()
 
# CPU time (only time spent computing)
cpu_start = time.process_time()
 
# Do some work
total = sum(i * i for i in range(10_000_000))
time.sleep(1)  # This won't count in CPU time
 
wall_elapsed = time.perf_counter() - wall_start
cpu_elapsed = time.process_time() - cpu_start
 
print(f"Wall time: {wall_elapsed:.2f}s")
print(f"CPU time: {cpu_elapsed:.2f}s")

import time
 
# Timezone offset in seconds
print(time.timezone)     # e.g., 18000 (5 hours)
print(time.altzone)      # DST offset
 
# Timezone name
print(time.tzname)       # ('EST', 'EDT')
 
# Is DST in effect?
print(time.daylight)     # 1 if DST exists
 
# For current time
t = time.localtime()
print(t.tm_isdst)        # 1 if DST active

ts = time.time()
s = time.strftime("%Y-%m-%d %H:%M:%S", time.localtime(ts))

s = "2026-03-21 14:30:00"
t = time.strptime(s, "%Y-%m-%d %H:%M:%S")
ts = time.mktime(t)

import time
 
def rate_limited_work(items, rate_per_second):
    interval = 1.0 / rate_per_second
    for item in items:
        start = time.monotonic()
        process(item)
        elapsed = time.monotonic() - start
        if elapsed < interval:
            time.sleep(interval - elapsed)

# time: raw timestamp
import time
ts = time.time()
 
# datetime: human-friendly
from datetime import datetime
dt = datetime.now()