What is an ISP proxy and how is it different from a datacenter proxy?

This guide separates the two types at the ASN level, shows how to check which class an IP falls into, and summarizes in a table which one fits which job. The examples use the WeProxy gateway gw.weproxy.com.tr:8989, with USER and PASSWORD as credential placeholders. For an overview of all four proxy types, see the residential, mobile, datacenter and ISP comparison.

What is an ISP proxy and how does it differ from a datacenter proxy?

Every public IPv4 block belongs to an autonomous system (AS) and is announced to the internet under that AS number (ASN). A home internet provider announces the blocks it hands out to subscribers under its own ASN. A cloud or hosting company announces the blocks it assigns to servers under its own ASN. When a target site receives a request, it classifies the IP based on this record.

With a datacenter proxy the chain is consistent: the server is in a data center and the IP is registered to the hosting provider's ASN. The target looks at the IP and easily concludes that "this address comes from a server".

With an ISP proxy this chain is split on purpose. The IP block is registered under a consumer ISP's ASN, but the machine carrying the traffic usually runs in a data center on a high-bandwidth link. The result: a reputation close to a residential IP, with speed and stability close to a datacenter. Because the IP is not a device owned by a real subscriber, residential pool issues such as the exit device going offline do not occur.

The third difference is assignment. An ISP proxy is almost always static: the same IP stays with you for days or weeks. A datacenter proxy comes both static (dedicated IP) and rotating (IP drawn from a pool).

What is an ASN and how does a target site tell the IP type?

An ASN is the number that represents a network's routing policy; its definition and usage rules are in RFC 1930. For example, AS16509 belongs to Amazon and AS14061 to DigitalOcean, while AS9121 announces Türk Telekom's and AS7922 Comcast's subscriber networks. A request from the first two most likely came from a server; one from the last two most likely came from a subscriber.

Bot protection systems and IP intelligence databases use this information in several layers:

• ASN class: whether the AS is labeled as hosting, ISP, mobile carrier or enterprise. In registries such as PeeringDB, the network type field shows this distinction.
• Range history: spam, bot and abuse signals previously seen from the same block.
• Context consistency: whether the IP's country matches the browser language, time zone and account history.

The ASN class is the first and cheapest filter. Many sites apply extra verification to traffic from hosting ASNs, or close flows such as sign-up, login and checkout to it entirely. An ISP proxy passes this first filter; it does not solve the second and third layers by itself. An abused ISP IP loses reputation too.

How do you check whether an IP is ISP or datacenter?

You can verify in three ways whether a proxy you bought or are testing really falls into the ISP class. In each case you first need the proxy's exit IP. The proxy address you connect to and the address the target sees do not have to be the same.

With the IP lookup tool

Open the My IP tool through the proxy and note the exit IP. Then enter that address into the IP lookup tool and look at the ASN and organization details. If the organization is a home or mobile internet operator, the IP is in the ISP class. If it is a cloud, hosting or server company, it is in the datacenter class.

With whois on the command line

Team Cymru's whois service returns the ASN, BGP prefix, country and AS name for an IP in a single line:

# 1) Get the exit IP through the proxy
IP=$(curl -sS -x "http://USER:[email protected]:8989" https://api.ipify.org)
echo "$IP"

# 2) Look up the ASN and AS name of this IP
whois -h whois.cymru.com " -v $IP"

The AS Name column in the output settles most cases. If the name alone is not enough, search the ASN on PeeringDB and check the network type field.

Bulk check with Python

If you bought several static IPs, use a script instead of checking each by hand. The example below fetches the exit IP for each proxy and prints the AS details from a whois query:

import socket
import requests

PROXIES = [
    "http://USER:[email protected]:8989",
    # add the other static IPs from your dashboard here
]

def asn_info(ip):
    with socket.create_connection(("whois.cymru.com", 43), timeout=10) as s:
        s.sendall(f" -v {ip}\r\n".encode())
        data = b""
        while chunk := s.recv(4096):
            data += chunk
    return data.decode().strip().splitlines()[-1]

for proxy in PROXIES:
    ip = requests.get(
        "https://api.ipify.org",
        proxies={"http": proxy, "https": proxy},
        timeout=(10, 30),
    ).text.strip()
    print(ip, "->", asn_info(ip))

For static products, connection details (IP, port, username) are shown per product in the dashboard; fill the list from there. You can also confirm that the proxy works in general with the proxy checker.

ISP proxy vs datacenter proxy comparison table

The most important row is the first one. Most of the other differences follow from which ASN the IP is registered to. For the general difference between residential and datacenter, see the residential vs datacenter article.

Where does an ISP proxy win?

The advantage of an ISP proxy is that it can carry the same identity for a long time without interruption. If the value of an account or session depends on how long it lives, an ISP proxy comes out ahead.

• Long-lived accounts: social media, marketplace seller dashboards and SaaS accounts record the IP and ASN at every login. Logging in from the same ISP IP for weeks triggers fewer checks than arriving from a different hosting IP each time. For this type of work, see the social media use case page.
• E-commerce sessions: cart, address and payment steps progress within one session. If the IP changes mid-flow, the site may reset the session or ask for extra verification. A static ISP IP reduces this risk.
• Checkout stability: in busy, time-critical flows such as limited-stock product drops and ticket sales, the checkout step is the most tightly inspected point. The problem here is usually not speed but the identity changing during the session. The near-datacenter latency of an ISP proxy and its fixed identity work together at this step.
• Ad accounts: ad dashboards are sensitive to sudden changes in the network used to log in. Managing an ad account from the same ISP IP every time makes account security checks more predictable. For ad preview and review work, the ad verification page adds guidance.

In these scenarios, what matters is that the IP stays with you. A sticky residential session does a similar job, but only for as long as the pool allows; in the WeProxy residential pool this goes up to 24 hours. For the difference between session models, read the sticky vs rotating guide.

The platform's terms of service apply to account management and checkout flows. A site that forbids multiple accounts, exceeding purchase limits or bulk-reserving stock enforces those rules regardless of IP type. Use of WeProxy is subject to the acceptable use rules.

When does a datacenter proxy make more sense?

The advantage of a datacenter proxy is volume, speed and predictable cost. If the target does not question the IP type, paying extra for an ISP IP buys nothing.

• Bulk public data: product listings, price pages and open catalogs do not always use aggressive IP filtering. Here a rotating datacenter proxy that changes IP per request is fast and economical. For details, see the web scraping page.
• Your own APIs and systems: if you access your own server, a partner's API or a dashboard protected by an IP whitelist, the target already knows your IP. A static datacenter proxy with a fixed ASN and location is enough for this.
• Speed-critical, unprotected targets: in short-response, high-frequency jobs such as uptime monitoring, CDN checks and SEO rank tracking, latency is the main metric.
• Testing and development: you do not need to burn expensive IPs while building a scraper's logic. Once the flow is stable, only the protected steps move to ISP or residential IPs.

If the target starts filtering hosting ASNs with 403 or CAPTCHA, the datacenter advantage ends. At that point, change the IP type instead of forcing the same job with more datacenter IPs. To tell 403 apart from 429, see the proxy error codes guide; 429 is a rate problem and can often be fixed without changing the IP type.

How do the cost models differ: per IP or per GB?

The two types are priced on different logic, and the comparison should follow that logic. Since figures change, you can find current starting packages on the product pages; here we compare only the models.

• ISP proxy: billed per IP, monthly. What you pay for is not traffic but holding an IP for a set period. It makes sense for jobs that run a small number of identities for a long time.
• Static datacenter: also billed per IP, monthly; at WeProxy this product lists bandwidth as unlimited. It suits fixed jobs that move a lot of traffic but are not identity-sensitive.
• Rotating datacenter: billed per GB. You pay for traffic volume, not IP count; each request can exit from a different IP.

The right measure is not the IP price but the cost per successful operation. A datacenter IP may be cheap, but if the target blocks half of the requests, retries, CAPTCHAs and account recovery add to the cost. Conversely, on an unprotected target the extra paid for an ISP IP gains nothing.

A mixed pipeline often gives the most efficient result: bulk and unprotected steps run on rotating datacenter, sensitive steps such as login and checkout run on an ISP proxy.

Is an ISP proxy the same as a residential proxy?

No. Both can share the same ASN class, but the infrastructure differs. Residential proxy traffic passes through the devices of real subscribers; an ISP proxy sends an IP registered to an ISP ASN out of a server in a data center.

In practice this difference has three consequences. Residential pools are very large and offer city-level targeting; with an ISP proxy, the number of IPs and locations is limited to the product card. A residential exit device can go offline; an ISP proxy runs on a server, so this interruption does not happen. Residential traffic is usually billed per GB, an ISP proxy per IP.

If you need wide geography and frequent IP changes, a rotating residential proxy fits better. If you need to keep a small number of identities for a long time, consider an ISP proxy or a static residential proxy.

How to choose ISP and datacenter products at WeProxy?

Before choosing, check four details on the product cards: location, protocol, session length and concurrency.

Location. The Static ISP IPv4 Proxy currently lists the United States as its location. For static datacenter IPv4, the listed countries are the United States, the United Kingdom, the Netherlands, Germany and Canada. Rotating datacenter IPv4 has a wider list that also includes Türkiye. If you need a static ISP-type IP exiting in Türkiye, look at the static residential product, which shows its IP type as "ISP IPv4" and lists a Türkiye location.

Protocol and UDP. All three products support HTTP and SOCKS5. UDP is not listed on the ISP proxy card. For jobs that require UDP (gaming, VoIP), the static residential card lists SOCKS5 + UDP for locations outside Türkiye; details are in the UDP proxy guide. Authentication works on all packages with username/password and IP whitelist, over both HTTP and SOCKS5.

Session length. With an ISP proxy, the IP stays fixed for up to 30 days. Rotating datacenter offers both sticky and rotating modes, plus ASN and city targeting.

Concurrency. Packages have no limit on threads or concurrent sessions. The target site's own rate limit is a separate matter; if you get 429, lower concurrency.

A short decision sequence:

1. Does the target block hosting ASNs? Try with a datacenter IP; if you get 403 or CAPTCHA, the answer is yes.
2. Must the job carry the same identity for days? If yes, an ISP proxy or static residential.
3. Is the job high-volume and sessionless? If yes, rotating datacenter.
4. Is the target your own system or does it use an IP whitelist? If yes, static datacenter.
5. After purchase, check the exit IP with IP lookup and confirm the ASN is in the class you expect.

An ISP proxy is for jobs that must pass the hosting ASN filter without giving up datacenter speed. A datacenter proxy stays faster and more economical wherever the target does not care about IP type. Base the decision not on the product label but on testing the target's behavior and verifying the exit ASN.