HTTP defines a rich set of caching headers that control how responses are stored and reused. `Cache-Control: max-age=3600` tells clients to use a cached copy for up to one hour. `ETag` and `Last-Modified` headers enable conditional requests: the client sends `If-None-Match` or `If-Modified-Since` headers, and the server responds with 304 Not Modified (no body, just reconfirm the cache is valid) if the content has not changed.

For scrapers, HTTP caching is a double-edged tool. On one hand, respecting cache headers reduces unnecessary requests to the target server (polite and efficient). On the other hand, scraping platforms should validate cache freshness before returning cached data, especially for price monitoring or news aggregation where staleness matters.

Some anti-bot systems manipulate cache headers to force scrapers to make more requests (disabling caching) or to detect scrapers that ignore cache control (never requesting fresh content). Understanding cache semantics helps scrapers behave like real browsers.

Examples

# Check if response is fresh or from cache
import requests

response = requests.get("https://example.com/prices")
cache_control = response.headers.get("Cache-Control", "")
age = response.headers.get("Age", "0")  # seconds since cached
etag = response.headers.get("ETag")
print(f"Cache-Control: {cache_control}, Age: {age}s, ETag: {etag}")

HTTP Cache

Examples

Related Terms

Extract HTTP Cache data from any website

Your first scrape.
Sixty seconds.

Examples

Related Terms

Extract HTTP Cache data from any website

Your first scrape. Sixty seconds.

Your first scrape.
Sixty seconds.