What is bot detection, and how does it work?

Bots generate nearly half of all traffic (49.6%) on the internet. While not all bot traffic is malicious, many websites use bot detection tools to identify and block certain types of bots from accessing their content. Automated bots and the tools that identify them are becoming more sophisticated all the time, using techniques like machine learning and AI to both avoid detection and enhance detection capabilities.

Note: Bot traffic can also visit apps and other online services, but for simplicity we will refer to websites, rather than all online services.

• What is bot detection
• How does bot detection work?
• Bot detection example
• What is the purpose of bot detection
• Bot detection tools
• How bot detection affects web scraping
• How to avoid bot detection

What is bot detection?

Bot detection is the process of identifying bot traffic by distinguishing it from traffic generated by real people using the website. As a result, bots that wish to avoid detection (and the consequences of bot detection, like IP bans) attempt to mimic human behavior. This has led to an ongoing arms race between bot developers and the people who create bot detection software.

Primitive bot detection methods (like CAPTCHA), don’t always work against advanced bots, so people who develop bot detection tools need to create increasingly sophisticated solutions. For example, some bot detection tools now use machine learning to create behavioral models that learn and adapt to bots as they evolve, or implement algorithms that detect unusual or unexpected behavior.

As bot detection methods become more sophisticated, there is a growing trend towards developing more autonomous bots that can operate with greater independence and intelligence. This is made possible by advancements in artificial intelligence and machine learning technologies, which enables bots to better mimic human behavior, teach themselves, and adapt to new situations.

Learn about SOAX’s AI Scraper

How does bot detection work?

Bot detection relies on a combination of tools and techniques to differentiate between human users and automated bots. Websites use methods that analyze user behavior, traffic patterns, and technical details to determine the likelihood of bot activity.

Some of the techniques that bot detection tools use includes:

• Behavioral analysis
• Browser and device fingerprinting
• IP address analysis
• CAPTCHA challenges
• Traffic analysis

Behavioral analysis

Behavioral analysis focuses on analyzing user interactions and patterns to look for indications of bot-like behavior. It looks at factors like:

• Mouse movements
• Clicks
• Scrolling speed
• Typing patterns
• Navigation paths
• Time spent on page

Some advanced bot detection methods use machine learning and AI to develop more sophisticated software that can learn and adapt to the evolving behavior of bots. These models can analyze huge amounts of data to identify very subtle patterns and anomalies that distinguish bots from humans.

Browser and device fingerprinting

Browser fingerprinting is a method websites use to create a unique "fingerprint" of a visitor's browser and device configuration. This fingerprint is based on various attributes like:

• Browser type
• Version
• Operating system
• Screen resolution
• Installed fonts
• Plugins

Websites can also examine hardware characteristics like CPU, GPU, and network adapters to create a unique device fingerprint. They can use the device fingerprint in combination with a browser fingerprint to improve bot detection accuracy.

IP address analysis

Every device connected to the internet has a unique IP address. Websites can log your IP address when you access their content, which they can then use to track and monitor your activity. They can use this information to analyze your IP address and determine whether you are a real human or a bot, by looking at:

• IP reputation on services that track the history of different IP addresses
• Multiple requests from the same IP address, which can indicate automated activity
• Geolocation anomalies, such as traffic originating from unexpected or unusual locations compared to the website’s typical audience
• Databases of known bot networks or data centers associated with bot activity

CAPTCHA challenges

CAPTCHA works by presenting users with challenges that are easy for humans to solve but difficult for bots. 

Websites will usually present these challenges once they have already detected bot-like activity, and want the user to prove they are human. They do this to avoid a situation where everyone visiting a website has to solve challenges before accessing content, as that would cause frustration among real human visitors.

However, many bots are able to solve CAPTCHAs or even avoid them altogether by mimicking human behavior (so they don’t trigger them in the first place).

Traffic analysis

Bot detection relies on traffic analysis to examine patterns in website traffic to identify large surges of bot traffic. Websites track a number of traffic metrics like page views, unique visitors, session duration, and traffic sources to identify anomalies that could indicate bot activity, such as:

• Sudden spikes in traffic
• High bounce rates
• Short session durations
• Suspicious traffic sources

Websites can analyze these patterns in real time, so they can take immediate action in the event of a suspected bot attack. (For example, DDoS attacks.)

Bot detection in action (example)

If a user's interactions differ from typical human behavior by showing unusual or repetitive patterns, it will raise suspicion of bot activity. Some bot detection tools implement algorithms that can detect unusual or unexpected behavior, even when bots try to mimic human patterns.

For example, imagine a bot that’s programmed to browse an ecommerce website, add items to its cart, and proceed to checkout. It may try to mimic human behavior by:

• Randomizing clicks and navigation - by clicking on different product pages at varying intervals, scrolling through product descriptions, and adding items to the cart randomly
• Varying session duration - by spending different amounts of time on each page and in the checkout process, mimicking human browsing habits
• Using a common user agent - disguising itself as a popular web browser that many real users use

An anomaly detection algorithm that monitors the website’s traffic can analyze various aspects of the bot’s behavior and compare it to a database of normal patterns from real human interactions. Here’s how it might identify the bot:

• Bots can click on more products and navigate through pages much faster than a human.
• Even with randomized actions, bots can exhibit repetitive patterns in its checkout process, such as always selecting the same shipping options or payment method.
• Bots can be active outside usual shopping hours, such as late at night or early in the morning, when human users are less likely to browse.
• While bots might use a common user agent, the algorithm could detect inconsistencies in other technical details, such as the browser version or the operating system they claim to be running on.

Once the algorithm identifies a bot, the website could take action to prevent it from accessing the site:

• The bot could be presented with a CAPTCHA challenge to verify its humanness.
• The bot's access could be temporarily limited or slowed down to prevent it from overloading the website.
• The website might block the bot's IP address from accessing the website altogether.

What is the purpose of bot detection?

Bot detection helps website administrators maintain the security, integrity, and functionality of their websites.

Security

Bot detection helps keep websites safe from malicious bot. For example, some bad actors may deploy bots in an attempt to steal information from people’s accounts. In this instance, a bot detection system can block attempts to guess passwords using brute force attacks (trying every possible combination), and prevent unauthorized access to user accounts.

User experience

Bots can be annoying. For example, some people can deploy bots to leave spam or fake reviews on websites. This ruins the experience for real people who are trying to use the website as intended. Bot detection helps to prevent these spam bots, making the website more enjoyable for everyone.

Analytics

Bot traffic can mess with website data, making it hard for website administrators to understand how real people are using their site. Bot detection systems can filter out this fake traffic, so analytics platforms give more accurate data.

Bot detection tools

There are lots of bot detection systems that people can use to help them identify bot traffic on their websites. If you are a data professional who wants to scrape public data, you will encounter different types of bot detection tools depending on the websites you want to extract data from.

Larger, more complex websites often face sophisticated bot attacks and have the resources to invest in advanced bot detection tools. These tools use machine learning, behavioral analysis, and real-time traffic monitoring to identify and mitigate a wide range of bot threats.

In contrast, smaller websites with limited budgets may rely on simpler methods like CAPTCHA challenges and basic rate limiting. If data security is not a primary concern for them, they might choose to forgo expensive bot detection solutions altogether.

Some of the most advanced bot detection tools include:

• DataDome: Specializes in real-time bot protection, using AI and machine learning to identify and block bot traffic.
• Cloudflare: A comprehensive bot management tool that includes bot detection and mitigation, using machine learning, behavioral analysis, and a large datasets.
• Imperva: A web application firewall (WAF) with integrated bot protection features, using signatures, behavioral analysis, and reputation-based filtering to identify and block bots.

Data extraction platforms like SOAX are revolutionizing the field by using advanced machine learning and AI to outsmart even the newest anti-bot mechanisms. Our AI Scraper, for instance, can navigate any domain, and it adapts and learns from its encounters with various bot-detection tools to ensure you can have uninterrupted access to valuable public data.

Our Web Unblocker can also help you to avoid detection when web scraping by managing your proxies, implementing smart header management, and bypassing CAPTCHAs and other bot-detection methods.

How bot detection affects web scraping

Bot detection is the number one challenge facing anyone who wants to extract public data from websites. Websites use a number of techniques to identify and block automated bots, and that usually includes web scrapers. The techniques websites use can include:

• IP blocking and blacklisting
• CAPTCHA challenges
• Rate limiting
• Dynamic content changes

These techniques can throttle or entirely prevent scrapers from accessing a website, or – in the case of dynamic content changes – they can make it difficult for scrapers to consistently and reliably extract data.

However, some data extraction tools can counter these challenges. At SOAX, we have products to automatically rotate proxies, integrate with headless browsers, and mimic real human behavior to evade bot detection measures. By constantly adapting and evolving,  we can ensure uninterrupted access to valuable data, enabling businesses and researchers to gather the information they need for informed decision-making and staying ahead of the competition.

How to avoid bot detection

It’s important to have a number of tools at your disposal to help you avoid all the different bot detection mechanisms you can encounter. At SOAX, we offer a comprehensive suite of products designed to help you overcome every challenge.

Residential proxies

Residential proxies allow you to route your requests through real residential IP addresses, making your traffic appear more like a genuine human user. This helps to reduce the risk of a website identifying your web scraper as a bot. At SOAX, we have a huge pool of unique, whitelisted residential IP addresses, from all over the world, so you can scrape data from anywhere.

Automatically rotating proxies

When you use rotating proxies with your web scraper, it means that your scraper constantly changes the IP address it uses for its requests. This makes your automated traffic look like multiple users accessing a site from different locations. As a result, it makes it much harder for websites to identify your scraping activity.

Websites often also implement rate limits to restrict the number of requests a single IP address can make in a certain timeframe. Rotating proxies allow you to distribute your requests across multiple IP addresses, effectively bypassing rate limits and making your data extraction faster.

With SOAX, you can set your proxies to automatically rotate at a rate that suits your needs, so you’ll never have to deal with rate limiting or IP bans again.

Fingerprint management

Our scraping APIs and Web Unblocker rotate your browser fingerprints to make it difficult for websites to identify your bot activity. We do this by varying attributes like user agent, screen resolution, and installed plugins, so you can effectively mask your scraping activity.

Intelligent retry and error handling

The SOAX AI Scraper detects errors and intelligently retries failed requests. When it encounters an error, it retries its request using a different IP address, or adjusts the request parameters to avoid repeated failures. This minimizes downtime and maximizes the success rate of your data extraction efforts.

Smart header management

Websites can use information in your headers to detect and block bots. Web Unblocker uses smart header management to automatically configure and rotate headers such as referrers, cookies, and authorization tokens. By dynamically adjusting these headers, your requests appear to come from a typical human user, which reduces the likelihood of the website detecting your scraping activity.

Machine learning and AI-powered scrapers

Our AI Scraper adapts to changing website structures and anti-bot measures. It continuously learns from past interactions and adjusts its behavior to navigate complex websites and extract data accurately. The AI Scraper ensures that your scraping operations remain efficient and resilient against evolving detection techniques.