Subnet Diversity
Subnet diversity is how widely a proxy pool spreads across distinct network blocks, usually counted at the /24 level and, one layer up, across autonomous systems. It is the number that matters, and it is not the number vendors advertise. Pool size counts addresses. Subnet diversity counts the independent places those addresses live.
The distinction is load-bearing because most rate limiting and blocklisting operates above the single address. A defender that bans one IP per offense loses immediately against rotation, so the practical response is to widen the unit: throttle the /24, challenge the /24, or in the harder cases score the whole ASN. Under that regime, 10,000 IPs distributed across forty /24s behaves like roughly forty IPs once you attract attention. The first blocked exit takes its 253 neighbors with it. Teams hit this as a sudden cliff rather than a gradual decline, which is what makes it hard to diagnose from success-rate graphs alone: throughput holds fine until the target's threshold trips, then a large fraction of the pool goes dark at once.
Measuring it is straightforward and nobody does it. Run traffic through the pool for a sampling window long enough to exercise rotation, log the exit IP of every request, group by the first three octets, and plot the distribution. Two numbers fall out: how many distinct /24s you actually saw, and what share of requests the top ten accounted for. Do it per country, since a vendor with genuine breadth in the US often has a dozen subnets in the markets you actually need. Vendors sidestep this by quoting totals, and the totals are frequently honest and irrelevant at the same time.
So write the right number into the contract. Distinct /24s observed per country per hour, and a cap on the share any single /24 may serve, are commitments a vendor can meet or decline. Total pool size is not, because you cannot audit it and it does not predict behavior under blocking. Structure the trial so concentration surfaces before you commit spend: sample for a week, on the targets you care about, and push hard enough to trigger the defenses you will meet in production. A pool that looks identical to a better one at low volume separates fast at high volume.
Tools that handle subnet diversity
4 tools in the webscrape.dev directory are commonly used for subnet diversity workflows, spanning proxy networks. Each is reviewed independently with pricing and editorial assessment.
Rayobyte, operated by Sprious LLC out of Lincoln, Nebraska, is a proxy network and web-scraping infrastructure provider that has been in business for more than 10 years. Its lineup includes residential proxies (40M+ IPs), static and rotating ISP and datacenter proxies, mobile proxies (400K+ static IPs), a Web Unblocker anti-bot endpoint, a Web Scraping API with a free monthly tier, and rayobrowse, a self-hosted Chromium-based browser tool. The company says it processes more than 20 petabytes of traffic monthly with over 50 full-time staff. Pricing is self-serve and pay-as-you-go, with a usage dashboard on its site.
Webshare is a proxy infrastructure provider founded in 2018. It sells three proxy product lines: datacenter proxies (400,000+ IPs), static residential/ISP proxies sourced from providers like Comcast and AT&T, and rotating residential proxies (80 million+ IPs across 195 countries) with country and city targeting. Access is through a REST API, an account dashboard, and a Chrome extension, with a free tier of 10 datacenter proxies and no credit card required. The company reports more than 60,000 paid customers and over 650 billion monthly proxy requests.
Mars Proxies is a proxy network with four proxy types: residential (1M+ IPs across 195 countries, from $1.65/GB), datacenter (about 100K IPs, from $0.89/proxy), ISP/dedicated (from $1.35/proxy), and mobile 4G/5G/LTE (from $2.83/day). Plans are pay-as-you-go or subscription-based, with no contracts or traffic expiration. It ships an API with Python, Node.js, and cURL examples, browser extensions for Chrome and Firefox, mobile apps for Android and iOS, an IP lookup tool, a proxy checker, city-level geo-targeting, and HTTP/HTTPS plus SOCKS5 support.
ProxyRack is a proxy service with residential, datacenter, mobile, and ISP-style proxies, a residential VPN, and a Web Scraping API. IPs rotate or hold a sticky session across 140+ country locations, with HTTP, SOCKS, and UDP protocol support. A self-service dashboard shows live usage reporting, and help.proxyrack.com hosts documentation plus a GitHub org of usage examples in multiple languages. Plans run flat monthly rates rather than pure pay-per-GB: $49.95/mo for residential, $50/mo for mobile, $100/mo for datacenter. The company says it has 3,000+ customers.