What is BLEXBot?
BLEXBot is the crawler for WebMeUp's backlink checker tool. It focuses on discovering and analyzing backlinks to help SEO professionals and website owners understand their link profiles. The bot contributes to WebMeUp's backlink database, which offers both free and paid tiers of backlink analysis. BLEXBot operates with respect for server resources and robots.txt directives. While not as large as major SEO platforms, WebMeUp provides accessible backlink data that's particularly useful for smaller websites and SEO practitioners.
User Agent String
Mozilla/5.0 (compatible; BLEXBot/1.0; +http://webmeup.com/crawler/)
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How to Control BLEXBot
Block Completely
To prevent BLEXBot from accessing your entire website, add this to your robots.txt file:
User-agent: BLEXBot
Disallow: /
Block Specific Directories
To restrict access to certain parts of your site while allowing others:
User-agent: BLEXBot
Disallow: /admin/
Disallow: /private/
Disallow: /wp-admin/
Allow: /public/
Set Crawl Delay
To slow down the crawl rate (note: not all bots respect this directive):
User-agent: BLEXBot
Crawl-delay: 10
How to Verify BLEXBot
Verification Method:
Check user agent and behavior
Learn more in the official documentation .
Detection Patterns
Multiple ways to detect BLEXBot in your application:
Basic Pattern
/BLEXBot/i
Strict Pattern
/^Mozilla/5\.0 \(compatible; BLEXBot/1\.0; \+http\://webmeup\.com/crawler/\)$/
Flexible Pattern
/BLEXBot[\s\/]?[\d\.]*?/i
Vendor Match
/.*WebMeUp.*BLEXBot/i
Implementation Examples
PHP
Python
JavaScript
.htaccess
Nginx
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function detect_blexbot() {
$user_agent = $_SERVER['HTTP_USER_AGENT'] ?? '';
$pattern = '/BLEXBot/i';
if (preg_match($pattern, $user_agent)) {
// Log the detection
error_log('BLEXBot detected from IP: ' . $_SERVER['REMOTE_ADDR']);
// Set cache headers
header('Cache-Control: public, max-age=3600');
header('X-Robots-Tag: noarchive');
// Optional: Serve cached version
if (file_exists('cache/' . md5($_SERVER['REQUEST_URI']) . '.html')) {
readfile('cache/' . md5($_SERVER['REQUEST_URI']) . '.html');
exit;
}
return true;
}
return false;
}
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import re
from flask import request, make_response
def detect_blexbot():
user_agent = request.headers.get('User-Agent', '')
pattern = r'BLEXBot'
if re.search(pattern, user_agent, re.IGNORECASE):
# Create response with caching
response = make_response()
response.headers['Cache-Control'] = 'public, max-age=3600'
response.headers['X-Robots-Tag'] = 'noarchive'
return True
return False
class BLEXBotMiddleware:
def __init__(self, get_response):
self.get_response = get_response
def __call__(self, request):
if self.detect_bot(request):
# Handle bot traffic
pass
return self.get_response(request)
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const express = require('express');
const app = express();
// Middleware to detect BLEXBot
function detectBLEXBot(req, res, next) {
const userAgent = req.headers['user-agent'] || '';
const pattern = /BLEXBot/i;
if (pattern.test(userAgent)) {
// Log bot detection
console.log('BLEXBot detected from IP:', req.ip);
// Set cache headers
res.set({
'Cache-Control': 'public, max-age=3600',
'X-Robots-Tag': 'noarchive'
});
// Mark request as bot
req.isBot = true;
req.botName = 'BLEXBot';
}
next();
}
app.use(detectBLEXBot);
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RewriteEngine On
RewriteCond %{HTTP_USER_AGENT} BLEXBot [NC]
RewriteRule .* - [F,L]
RewriteCond %{HTTP_USER_AGENT} BLEXBot [NC]
RewriteCond %{REQUEST_URI} !^/static/
RewriteRule ^(.*)$ /static/$1 [L]
SetEnvIfNoCase User-Agent "BLEXBot" is_bot=1
<If "%{HTTP_USER_AGENT} =~ /BLEXBot/i">
Header set Cache-Control "public, max-age=3600"
Header set X-Robots-Tag "noarchive"
</If>
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map $http_user_agent $is_blexbot {
default 0;
~*BLEXBot 1;
}
server {
if ($is_blexbot) {
return 403;
}
location / {
if ($is_blexbot) {
root /var/www/cached;
try_files $uri $uri.html $uri/index.html @backend;
}
try_files $uri @backend;
}
location @backend {
if ($is_blexbot) {
add_header Cache-Control "public, max-age=3600";
add_header X-Robots-Tag "noarchive";
}
proxy_pass http://backend;
}
}
Should You Block This Bot?
Recommendations based on your website type:
Site Type
Recommendation
Reasoning
E-commerce
Optional
Evaluate based on bandwidth usage vs. benefits
Blog/News
Allow
Increases content reach and discoverability
SaaS Application
Block
No benefit for application interfaces; preserve resources
Documentation
Selective
Allow for public docs, block for internal docs
Corporate Site
Limit
Allow for public pages, block sensitive areas like intranets
Advanced robots.txt Configurations
E-commerce Site Configuration
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User-agent: BLEXBot
Crawl-delay: 5
Disallow: /cart/
Disallow: /checkout/
Disallow: /my-account/
Disallow: /api/
Disallow: /*?sort=
Disallow: /*?filter=
Disallow: /*&page=
Allow: /products/
Allow: /categories/
Sitemap: https://example.com/sitemap.xml
Publishing/Blog Configuration
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User-agent: BLEXBot
Crawl-delay: 10
Disallow: /wp-admin/
Disallow: /drafts/
Disallow: /preview/
Disallow: /*?replytocom=
Allow: /
SaaS/Application Configuration
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User-agent: BLEXBot
Disallow: /app/
Disallow: /api/
Disallow: /dashboard/
Disallow: /settings/
Allow: /
Allow: /pricing/
Allow: /features/
Allow: /docs/
Quick Reference
User Agent Match
BLEXBot
Robots.txt Name
BLEXBot
Category
seo
Respects robots.txt
Yes