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Scraper Blocking Knowledgebase

Web scraping blocking is an increasingly common and complex challenge faced by developers. Websites implement various anti-bot techniques to prevent automated scraping, which can hinder data extraction efforts.

There are many different aspects when it comes to identifying web scrapers which with proper understanding can be addressed in almost any web scraping project. To start see our overall introduction to all methods of scraper detection:

5 Tools to Scrape Without Blocking and How it All Works

Tutorial on how to avoid web scraper blocking. What is javascript and TLS (JA3) fingerprinting and what role request headers play in blocking.

For more on scraper blocking and how to bypass it, see the resources below 👇

Web scraping - what is HTTP 499 status code?

Response error 499 generally means the server has closed the connection unexpectedly. This could mean the client is being blocked. Here's how to fix it.

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Web scraping - what is HTTP 503 status code?

Response error 503 generally means the server is temporarily unavailable however it could also mean blocking. Here's how to fix it.

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Web scraping - what is HTTP 429 status code?

Response error code 429 means the client is making too many requests in a given time span and should slow down. Here's how to avoid it.

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What is 444 status code and how to avoid it?

Response error code 444 means the server has unexpectedly closed connection. This could mean the web scraper is being blocked.

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Web scraping - what is HTTP 403 status code?

Response error 403 generally means the client is being blocked. This could mean invalid request options or blocking. Here's how to fix it.

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Web scraping - what is HTTP 520 status code?

Response error 502 generally means the server cannot create a valid response. This could also mean the client is being blocked. Here's how to fix it.

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What is Cloudflare Error 1009?

Cloudflare is a popular web scraping blocking service and error 1009 access denied is a popular error for web scraper blocking. Here's how to avoid it.

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What is Cloudflare Error 1020?

Cloudflare error 1020 access denied is a common web error when web scraping caused by Cloudflare anti scraping service. Here's how to avoid it.

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Articles Related to Scraper Blocking

How to Screenshot Cloudflare-Protected Websites

Learn how to capture screenshots of Cloudflare-protected websites using Scrapfly Screenshot API, Puppeteer, and Selenium. Includes code examples and troubleshooting.

SCREENSHOTS PYTHON BLOCKING

How to Screenshot Cloudflare-Protected Websites

Automatic Failover Strategies for Reliable Data Extraction

A deep dive into automatic failover strategies like retries, backoff, and circuit breakers to build resilient and reliable web scrapers that can handle network errors, blocks, and other common failures.

BLOCKING

Automatic Failover Strategies for Reliable Data Extraction

Bypass Proxy Detection with Browser Fingerprint Impersonation

Stop proxy blocks with browser fingerprint impersonation using this guide for Playwright, Selenium, curl-impersonate & Scrapfly

PROXIES SELENIUM PLAYWRIGHT PUPPETEER BLOCKING

Bypass Proxy Detection with Browser Fingerprint Impersonation

What is Rate Limiting? Everything You Need to Know

Discover what rate limiting is, why it matters, how it works, and how developers can implement it to build stable, scalable applications.

BLOCKING CRAWLING HTTP

What is Rate Limiting? Everything You Need to Know

How to Choose the Best Proxy Unblocker?

Learn how to choose the best proxy unblocker to access blocked websites. Explore proxies, VPNs, and Scrapfly for bypassing restrictions safely.

PROXIES BLOCKING

Alternatives to Cloudscraper to Bypass Cloudflare

Learn why Cloudscraper is outdated and explore modern alternatives for bypassing Cloudflare protections effectively and ethically.

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Alternatives to Cloudscraper to Bypass Cloudflare

What is Error 1015 (Cloudflare) and How to Fix it?

Discover why you're seeing Cloudflare Error 1015 and learn effective ways to resolve and prevent it.

BLOCKING HTTP

What is Error 1015 (Cloudflare) and How to Fix it?

HTTP Error 503 Service Unavailable and How to Fix it?

Understand what causes HTTP 503 errors, when they might indicate blocking, and how to effectively mitigate them.

API HTTP BLOCKING

HTTP Error 503 Service Unavailable and How to Fix it?

What is HTTP Error 429 Too Many Request and How to Fix it

HTTP 429 is an infamous response code that indicates request throttling or distribution is needed. Let's take a look at how to handle it.

HTTP BLOCKING

What is HTTP Error 429 Too Many Request and How to Fix it

What is CreepJS Browser Fingerprint and How to Bypass It

In this article, we will explore the inner workings of CreepJS, one of the prominent browser fingerprinting tools and how to bypass it.

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What is CreepJS Browser Fingerprint and How to Bypass It

How to Know What Anti-Bot Service a Website is Using?

In this article we'll take a look at two popular tools: WhatWaf and Wafw00f which can identify what WAF service is used.

BLOCKING TOOLS

How to Know What Anti-Bot Service a Website is Using?

Use Curl Impersonate to scrape as Chrome or Firefox

Learn how to prevent TLS fingerprinting by impersonating normal web browser configurations. We'll start by explaining what the Curl Impersonate is, how it works, how to install and use it. Finally, we'll explore using it with Python to avoid web scraping blocking.

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Use Curl Impersonate to scrape as Chrome or Firefox

FlareSolverr Guide: Bypass Cloudflare While Scraping

In this article, we'll explore the FlareSolverr tool and how to use it to get around Cloudflare while scraping. We'll start by explaining what FlareSolverr is, how it works, how to install and use it. Let's get started!

PYTHON TOOLS BLOCKING HTTP

FlareSolverr Guide: Bypass Cloudflare While Scraping

5 Proven Ways to Bypass CAPTCHA in Python

Captchas can ruin web scrapers but we don't have to teach our robots how to solve them - we can just get around it all!

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5 Proven Ways to Bypass CAPTCHA in Python

How to Bypass Kasada Anti-Bot When Web Scraping in 2026

In this article, we'll take a look at the popular anti-bot service Kasada. How does it detect web scrapers and bots and what can we do to prevent our scrapers from being detected?

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How to Bypass Kasada Anti-Bot When Web Scraping in 2026

What are Honeypots and How to Avoid Them in Web Scraping

Introduction to web honeypots, their types and functions and how they are used to identify and block web scrapers and bots and how to avoid them.

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What are Honeypots and How to Avoid Them in Web Scraping

How to Hide Your IP Address

In this article we'll be taking a look at several ways to hide IP addresses: proxies, tor networks, vpns and other techniques.

BLOCKING TOOLS PROXIES

Web Scraping Without Blocking With Undetected ChromeDriver

In this tutorial we'll be taking a look at a new popular web scraping tool Undetected ChromeDriver which is a Selenium extension that allows to bypass many scraper blocking techniques.

BLOCKING PYTHON TOOLS

Web Scraping Without Blocking With Undetected ChromeDriver

How to Avoid Scraper Blocking when Scraping Images

Introduction to scraper blocking when it comes to image scraping. What are some popular scraper blocking techniques and how to avoid them.

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How to Bypass Imperva Incapsula when Web Scraping in 2026

In this article we'll take a look at a popular anti bot service Imperva Incapsula anti bot WAF. How does it detect web scrapers and bots and what can we do to prevent our scrapers from being detected?

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How to Bypass Imperva Incapsula when Web Scraping in 2026

How to Bypass Datadome Anti Scraping in 2026

In this article we'll take a look at a popular anti bot service Datadome Anti Bot firewall. How does it detect web scrapers and bots and what can we do to prevent our scrapers from being detected?

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How to Bypass Datadome Anti Scraping in 2026

How to Bypass PerimeterX when Web Scraping in 2026

In this article we'll take a look at a popular anti scraping service PerimeterX. How does it detect web scrapers and bots and what can we do to prevent our scrapers from being detected?

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How to Bypass PerimeterX when Web Scraping in 2026

How to Bypass Akamai when Web Scraping in 2026

In this article we'll take a look at a popular anti bot service Akamai Bot Manager. How does it detect web scrapers and bots and what can we do to prevent our scrapers from being detected?

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How to Bypass Akamai when Web Scraping in 2026

How to Bypass Cloudflare When Web Scraping in 2026

Cloudflare offers one of the most popular anti scraping service, so in this article we'll take a look how it works and how to bypass it.

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How to Bypass Cloudflare When Web Scraping in 2026

How to Rate Limit Async Requests in Python

Quick tutorial on how to limit asynchronous python connections when web scraping. This can reduce and balance out web scraping speed to avoid scraping pages too fast and blocking.

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How to Rate Limit Async Requests in Python

Web Scraping With Node-Unblocker

Tutorial on using Node-Unblocker - a nodejs library - to avoid blocking while web scraping and using it to optimize web scraping stacks.

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How Javascript is Used to Block Web Scrapers? In-Depth Guide

Introduction to how javascript is used to detect web scrapers. What's in javascript fingerprint and how to correctly spoof it for web scraping.

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How Javascript is Used to Block Web Scrapers? In-Depth Guide

How TLS Fingerprint is Used to Block Web Scrapers?

TLS fingeprinting is a popular way to identify web scrapers that not many developers are aware of. What is it and how can we fortify our scrapers to avoid being detected?

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