What Is a Bot?

A bot is a software program that performs automated tasks on the internet, often mimicking human behavior. Bots handle roughly 40-50% of all web traffic. Some are helpful (like search engine crawlers), but a large portion is malicious: clicking on ads, scraping websites, filling out forms with fake data, or draining advertising budgets.

How do bots work?

A bot follows a set of programmed instructions to perform repetitive tasks much faster than any human could. At the simplest level, a bot sends HTTP requests to websites, reads the responses, and takes action based on what it finds. A price-monitoring bot, for example, visits product pages every few minutes and logs price changes.

More advanced bots simulate real browser behavior. They load JavaScript, move a mouse cursor, scroll through pages, and even solve basic CAPTCHAs. These sophisticated bots are harder to distinguish from real visitors because they generate realistic-looking traffic patterns.

Bots can run on a single machine or across thousands of compromised devices in a botnet. When distributed across many IP addresses, bot traffic becomes much harder to detect and block because each individual device looks like a normal visitor.

What types of bots exist?

Not all bots are harmful. The distinction between good and bad bots matters for anyone managing a website or running ad campaigns.

Legitimate bots

• Search engine crawlers: Googlebot, Bingbot, and similar crawlers index your website so it appears in search results. Blocking these would hurt your SEO.
• Monitoring bots: Uptime checkers and performance monitors that verify your site is accessible and loading correctly.
• Chatbots: Customer service bots on websites that answer common questions and route visitors to the right support channel.
• Feed fetchers: Bots that pull RSS feeds, news aggregators, or API data on a schedule.

Malicious bots

• Click fraud bots: Bots that click on pay-per-click ads to waste an advertiser’s budget. They target Google Ads, Meta Ads, and other platforms. According to ClickPatrol’s PPC fraud study, up to 21% of all PPC traffic comes from non-human sources.
• Scraper bots: Programs that copy content, pricing data, or product information from websites at scale. Competitors use these to monitor your pricing or steal your content.
• Credential stuffing bots: Bots that try stolen username/password combinations across multiple websites to break into accounts.
• Form spam bots: Automated programs that fill out contact forms, registration pages, and lead generation forms with fake data. This pollutes CRM systems and wastes sales teams’ time on junk leads.
• Click farm bots: Networks of bots (or low-paid workers with bots) that generate fake engagement: likes, follows, reviews, or ad clicks.

Why are bots a problem for advertisers?

For anyone running paid campaigns, bot traffic creates three specific problems.

Budget waste. Every bot click on a Google Ads campaign costs real money. If 15% of your clicks are from bots and you spend EUR 10.000 per month, that is EUR 1.500 going to clicks that will never convert into a customer.

Corrupted data. Bot visits pollute your analytics. They inflate click-through rates, skew geographic data, and create fake conversion events. When Google’s algorithm optimizes your campaigns based on this polluted data, it starts targeting more of the wrong audience. Your cost per acquisition goes up, and real performance goes down.

Wasted sales effort. Form spam bots generate leads that look real but go nowhere. Sales teams spend hours calling disconnected numbers and emailing addresses that bounce. ClickPatrol customers typically report 40-70% fewer junk leads after activating protection.

How can you detect bot traffic?

Identifying bots requires looking at multiple signals, not just IP addresses. Here are the key indicators:

• Abnormal session behavior: Visits lasting under 1 second, zero scroll depth, or identical navigation paths repeated hundreds of times.
• Suspicious technical fingerprints: Outdated or generic user agents, missing JavaScript execution, or device fingerprints that match known bot signatures.
• Traffic spikes from datacenter IPs: Legitimate users browse from residential ISPs. A sudden surge of traffic from cloud hosting providers like AWS or DigitalOcean is a strong indicator of bot activity.
• Geographic mismatches: If your ads target the Netherlands but you see a spike of clicks from countries you don’t advertise in, bots using proxy servers are likely responsible.

At ClickPatrol, we analyze over 800 data points per click to distinguish bots from real visitors with 99.97% accuracy. This includes behavioral signals, device characteristics, network data, and pattern matching against known fraud sources.

How can you protect your campaigns from bots?

There are several layers of protection available:

1. Google’s built-in filters: Google Ads has basic invalid click detection, but it catches only a fraction of sophisticated bot traffic. Google often identifies fraud after your budget has already been spent.
2. Manual IP exclusions: You can exclude specific IPs in Google Ads, but the platform limits you to 500 IPs per campaign. Modern bots rotate through thousands of addresses, making manual blocking ineffective.
3. CAPTCHA on forms: Helps reduce form spam but does nothing against ad click fraud. Advanced bots can also bypass basic CAPTCHAs.
4. Dedicated click fraud protection: Tools like ClickPatrol monitor every click in real time, automatically blocking fraudulent sources before they drain your budget. This is the most effective approach for protecting both ad spend and data quality.

Abisola

Meet Abisola! As the content manager at ClickPatrol, she’s the go-to expert on all things fake traffic. From bot clicks to ad fraud, Abisola knows how to spot, stop, and educate others about the sneaky tactics that inflate numbers but don’t bring real results.

View all posts by Abisola (Abisola)