A tool that check your proxies. Name your proxy file proxy.txt and put it in same file with the checker.

proxy_checker.py

import requests
import threading
import time


proxies = []
n = 0

fetch = open("proxy.txt", "r").read().splitlines()
for proxy in fetch:
    proxies.append(proxy)
    n += 1
def save(i):
    file = open("good_proxy.txt", "a")
    file.write(i + "\n")
    file.close()

def checker(i):
    try:
        global running
        global good
        global bad
        running += 1
    except:
        running = 0
        bad = 0
        good = 0
    s = requests.session()
    s.proxies = {
        'http':'http://'+i,
        'https':'https://'+i
    }
    try:
        rr = s.get(url, timeout=5)
        print(f'Valid => {i}\n')
        save(i)
        good += 1
    except:
        print(f'Not Valid => {i}\n')
        bad += 1
    running -= 1
many = len(proxies)
print(f"{many} Proxies To Be Checked.")
url = "https://www.google.com/humans.txt"
good = 0
bad = 0
running = 0
ch = 0
max = 25

for i in proxies:
    if running < max:
        x = threading.Thread(target=checker, args=(i,))
        x.start()
        ch += 1
    else:
        time.sleep(.1)