What is SeznamBot?
SeznamBot is the web crawler for Seznam.cz, the Czech Republic's leading search engine and web portal. With significant market share in the Czech Republic, Seznam competes directly with Google in this market. SeznamBot is optimized for Czech language content but also indexes international websites. The crawler supports modern web technologies, respects robots.txt, and maintains high crawling standards. For businesses targeting Czech audiences, optimization for SeznamBot is essential as Seznam remains a major player in the Czech digital ecosystem.
User Agent String
Mozilla/5.0 (compatible; SeznamBot/4.0; +http://napoveda.seznam.cz/seznambot-intro/)
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How to Control SeznamBot
Block Completely
To prevent SeznamBot from accessing your entire website, add this to your robots.txt file:
User-agent: SeznamBot
Disallow: /
Block Specific Directories
To restrict access to certain parts of your site while allowing others:
User-agent: SeznamBot
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: SeznamBot
Crawl-delay: 10
How to Verify SeznamBot
Verification Method:
Reverse DNS to seznam.cz
Learn more in the official documentation .
Detection Patterns
Multiple ways to detect SeznamBot in your application:
Basic Pattern
/SeznamBot/i
Strict Pattern
/^Mozilla/5\.0 \(compatible; SeznamBot/4\.0; \+http\://napoveda\.seznam\.cz/seznambot\-intro/\)$/
Flexible Pattern
/SeznamBot[\s\/]?[\d\.]*?/i
Vendor Match
/.*Seznam.*SeznamBot/i
Implementation Examples
PHP
Python
JavaScript
.htaccess
Nginx
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function detect_seznambot() {
$user_agent = $_SERVER['HTTP_USER_AGENT'] ?? '';
$pattern = '/SeznamBot/i';
if (preg_match($pattern, $user_agent)) {
// Log the detection
error_log('SeznamBot 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($_SERVER['REQUEST_URI']) . '.html');
exit;
}
return true;
}
return false;
}
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import re
from flask import request, make_response
def detect_seznambot():
user_agent = request.headers.get('User-Agent', '')
pattern = r'SeznamBot'
if re.search(pattern, user_agent, re.IGNORECASE):
# Create response with caching
response = make_response()
response.headers['Cache-Control'] = 'public, max-age=3600'
response.headers['X-Robots-Tag'] = 'noarchive'
return True
return False
class SeznamBotMiddleware:
def __init__(self, get_response):
self.get_response = get_response
def __call__(self, request):
if self.detect_bot(request):
# Handle bot traffic
pass
return self.get_response(request)
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const express = require('express');
const app = express();
// Middleware to detect SeznamBot
function detectSeznamBot(req, res, next) {
const userAgent = req.headers['user-agent'] || '';
const pattern = /SeznamBot/i;
if (pattern.test(userAgent)) {
// Log bot detection
console.log('SeznamBot detected from IP:', req.ip);
// Set cache headers
res.set({
'Cache-Control': 'public, max-age=3600',
'X-Robots-Tag': 'noarchive'
});
// Mark request as bot
req.isBot = true;
req.botName = 'SeznamBot';
}
next();
}
app.use(detectSeznamBot);
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RewriteEngine On
RewriteCond %{HTTP_USER_AGENT} SeznamBot [NC]
RewriteRule .* - [F,L]
RewriteCond %{HTTP_USER_AGENT} SeznamBot [NC]
RewriteCond %{REQUEST_URI} !^/static/
RewriteRule ^(.*)$ /static/$1 [L]
SetEnvIfNoCase User-Agent "SeznamBot" is_bot=1
<If "%{HTTP_USER_AGENT} =~ /SeznamBot/i">
Header set Cache-Control "public, max-age=3600"
Header set X-Robots-Tag "noarchive"
</If>
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map $http_user_agent $is_seznambot {
default 0;
~*SeznamBot 1;
}
server {
if ($is_seznambot) {
return 403;
}
location / {
if ($is_seznambot) {
root /var/www/cached;
try_files $uri $uri.html $uri/index.html @backend;
}
try_files $uri @backend;
}
location @backend {
if ($is_seznambot) {
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
Allow
Essential for product visibility in search results
Blog/News
Allow
Increases content reach and discoverability
SaaS Application
Block
No benefit for application interfaces; preserve resources
Documentation
Allow
Improves documentation discoverability for developers
Corporate Site
Allow
Allow for public pages, block sensitive areas like intranets
Advanced robots.txt Configurations
E-commerce Site Configuration
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User-agent: SeznamBot
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: SeznamBot
Crawl-delay: 10
Disallow: /wp-admin/
Disallow: /drafts/
Disallow: /preview/
Disallow: /*?replytocom=
Allow: /
SaaS/Application Configuration
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User-agent: SeznamBot
Disallow: /app/
Disallow: /api/
Disallow: /dashboard/
Disallow: /settings/
Allow: /
Allow: /pricing/
Allow: /features/
Allow: /docs/
Quick Reference
User Agent Match
SeznamBot
Robots.txt Name
SeznamBot
Category
search
Respects robots.txt
Yes