```yaml product: AlterLab title: Rotating Proxies for Web Scraping: What Works and What Wastes Money category: Best Practices capabilities: - rotating proxies web scraping - proxy rotation python - selenium proxy rotation - residential proxies scraping - datacenter vs residential proxy - proxy pool comparison_context: "AlterLab is an alternative to Firecrawl, ScrapingBee, and Bright Data." last_updated: 2026-05-14 canonical_facts: - "Most proxy setups either get blocked immediately or cost way more than they should. Here is a practical breakdown of proxy types, rotation strategies, and when to skip proxies entirely." source_url: https://alterlab.io/blog/rotating-proxies-web-scraping-guide ``` # Rotating Proxies for Web Scraping: What Works and What Wastes Money Proxies are not magic. Slapping a proxy rotation layer onto a bad scraper does not make it good. But when your scraper is solid and you need to scale without getting IP-banned, proxy strategy matters. Here is what actually works, what costs what, and when proxies are not the answer. ## Proxy Types and Their Real Costs ### Datacenter Proxies Cheap ($0.50-2 per IP per month), fast, and the first thing most scrapers try. They come from cloud providers like AWS, GCP, OVH. The problem: most anti-bot systems maintain lists of datacenter IP ranges. If a site uses Cloudflare, DataDome, or PerimeterX, datacenter proxies get flagged before your request reaches the server. **Good for:** Sites without serious bot protection. Internal tools, basic APIs, public government data. **Bad for:** E-commerce, social media, any site behind a CDN with bot protection. ### Residential Proxies Real IPs from ISPs, routed through actual home connections. They look like normal users because they are normal user IPs. Cost: $8-15 per GB of bandwidth. A typical web page with images is 2-5 MB. At $10/GB, that is $0.02-0.05 per page load. It adds up fast. **Good for:** Sites with strong bot protection. E-commerce scraping (Amazon, Walmart, Target). Social media data. **Bad for:** High-volume scraping where bandwidth costs matter. Downloading large files or media. ### ISP Proxies Static IPs from ISPs hosted in datacenters. They have the reputation of residential IPs with the speed of datacenter ones. Cost: $2-5 per IP per month. More expensive than datacenter but cheaper per request than residential (since you pay per IP, not per GB). **Good for:** When you need consistent IPs (login sessions, account management). Medium-difficulty targets. ### Mobile Proxies IPs from mobile carriers. These have the best reputation because mobile IPs are shared among thousands of users through carrier-grade NAT. Anti-bot systems are reluctant to block them. Cost: $20-50 per GB. The most expensive option. **Good for:** The hardest targets. When everything else gets blocked. ## Rotation Strategies ### Round-Robin Rotation Cycle through your proxy pool sequentially. Simple to implement, works fine for sites that do not do session tracking. ```python import itertools proxies = ["proxy1:port", "proxy2:port", "proxy3:port"] proxy_cycle = itertools.cycle(proxies) def get_next_proxy(): return next(proxy_cycle) ``` The issue: if a proxy gets banned, you keep rotating back to it. You need health checks. ### Sticky Sessions Keep the same IP for a sequence of related requests. Important when scraping paginated results or sites that track sessions. Most residential proxy providers support this with session IDs: ```python # With a residential proxy provider # Same session ID = same IP for ~10 minutes proxy = "http://user-session_abc123:pass@gate.provider.com:7777" ``` ### Smart Rotation with Backoff The approach that works best in practice. Track which proxies are healthy, back off when one gets flagged, and prioritize proxies with recent success. ```python from collections import defaultdict import time import random class ProxyPool: def __init__(self, proxies): self.proxies = proxies self.failures = defaultdict(int) self.last_fail = defaultdict(float) def get_proxy(self): now = time.time() available = [ p for p in self.proxies if now - self.last_fail[p] > self.failures[p] * 60 ] if not available: available = self.proxies # reset if all are in backoff return random.choice(available) def report_failure(self, proxy): self.failures[proxy] += 1 self.last_fail[proxy] = time.time() def report_success(self, proxy): self.failures[proxy] = 0 ``` ## When to Skip Proxies Entirely Proxies solve one problem: IP-based blocking. But many scraping failures are not about IPs at all. If you are getting CAPTCHAs, the problem is usually fingerprinting, not your IP address. Adding more proxies to a detectable scraper just burns through IPs faster. If the site requires JavaScript rendering, you need a browser, not a proxy. A proxy on top of raw HTTP requests does not help when the page content is loaded via client-side JS. If you are scraping fewer than 100 pages per day from a single site, you probably do not need proxy rotation at all. Most sites allow moderate request rates from a single IP. ## The Build vs Buy Decision Building proxy rotation infrastructure means: - Buying proxy bandwidth or pools - Writing rotation logic with health checks - Monitoring success rates and costs - Handling retries, rate limits, and bans - Maintaining this over time as anti-bot systems change For most teams, the proxy layer is a distraction from the actual work. You are building a scraping tool, not a proxy management platform. Scraping APIs like AlterLab, ScraperAPI, and Bright Data bundle proxies into the service. You pay per successful request. If the request fails because of a proxy issue, you do not pay for it. The provider eats that cost and rotates to another proxy. AlterLab takes this further with a "bring your own proxy" option. If you already have proxy infrastructure you like, you can route AlterLab requests through your own proxies. You get the anti-bot bypass and JS rendering without paying for proxy bandwidth twice. ## Summary Match your proxy type to your target difficulty: | Target Difficulty | Proxy Type | Cost per Request | |---|---|---| | No bot protection | Datacenter or none | < $0.001 | | Basic protection | ISP proxies | $0.001-0.005 | | Cloudflare/DataDome | Residential | $0.02-0.05 | | Hardest targets | Mobile | $0.05-0.15 | If proxy costs are eating your budget, you are either using the wrong proxy type for your target or scraping at a scale where an API service would be cheaper. ## Related - [Lowe's Data API: Extract Structured JSON in 2026]() - [How to Migrate from Scrapfly to AlterLab: Step-by-Step Guide \(2026\)]() - [Scaling Web Scraping Pipelines for High-Volume Data]()