ISP vs datacenter proxies: same rate card, different network

ISP vs datacenter proxies is a decision about whose network an address appears to belong to, and at ProxyForge it is not a decision about price. Both lines are static addresses on servers we operate, dedicated to one customer and billed per address per month, and both are sold on one published rate card. The difference is where the address comes from: an ISP address is leased to us by a consumer internet provider, while a datacenter address sits in a range registered to us and announced from our own network. Some targets act on that difference and many ignore it, so the useful question is which kind your target accepts, and you can answer it yourself before you commit to a term.

Below: what each class is, where the two lines differ, a paired test you can run on your own target, a decision procedure and the checks that confirm what you received. For the wider comparison that adds rotating residential and mobile, read residential vs ISP vs datacenter proxies.

The short answer

If the target accepts addresses from hosting networks at the pace you need, buy datacenter. On the same rate card and the same 100 Mbps port speed, it gives each address a lower median latency and a shorter replacement window. If the target blocks or challenges hosting ranges, if the flow has to read as a consumer connection, or if you need to name the consumer ISP when ordering, buy ISP. If neither line returns real content at your pace, the job is not suited to a static address of any class, and a rotating residential pool is what to try next.

What each one is: who holds the address and who announces it

Every IPv4 address carries two public facts: its registration, which a regional internet registry records as the organization holding the block, and its route, the autonomous system (AS) that announces the block to the rest of the internet. Proxy classes differ in those two facts, not in the hardware. ISP and datacenter proxies both run on servers in a rack, with no household device in the path.

Datacenter proxies are addresses in blocks registered to whoever runs the servers: a hosting company, a cloud platform or the proxy vendor itself. At ProxyForge it is us: datacenter ranges are registered to us, announced from our own ASN and served from facilities we contract directly, and nothing is resold. A registry lookup on any datacenter address you hold names us as the holder. For any other vendor's datacenter line, the same lookup tells you which of the three you are buying.

ISP proxies are addresses a consumer broadband provider leases to a proxy vendor, served from the vendor's servers rather than from a home connection. Ours are leased from consumer ISPs under commercial contract and hosted on our racks. What the registry and the routing table show for a leased block depends on how the lease is arranged, and vendors arrange it differently: the registration can stay with the ISP or be reassigned, and the route can be originated by the ISP or by the vendor's network. Vendors also market these addresses as static residential proxies, because the block comes from a consumer provider while the server behind it sits in a data center.

The consequence is narrow: a target that sorts addresses by holder and announcing network puts a hosting range in the hosting bucket and a block held and announced by a consumer provider in the access-network bucket. Everything that depends on how your client behaves applies to both alike.

ISP vs datacenter proxies side by side

The table lists the two lines as published on the ISP proxies and datacenter proxies product pages.

The rate ladder is the same on both lines. At the rates published on 16 October 2026, ten addresses held for a 30-day term cost $26.60 on either line (10 × $2.66, the 10-address rate), and a longer term takes a further discount on both. The ISP pricing and datacenter pricing pages carry the current ladder. With price held constant, the rows that differ are the ones to decide on: where the address comes from, port speed, latency, the replacement window and how a batch is spread across /24 blocks.

How targets treat each class

Targets rarely see the server behind an address. They classify it from what is quick to look up and from what they observe:

1. Registration and routing. Who holds the block and what kind of network announces it. Hosting ranges are easy to list, and some sites challenge or refuse them before a page is served.
2. IP-intelligence labels. Commercial databases tag ranges as hosting, ISP, business or mobile, largely from the first signal plus observed traffic. Some also tag ranges they believe are leased to proxy providers.
3. Per-address behavior. Request rate, timing and how often one address returns. A static address of either class builds a history here.
4. The client. Headers, TLS fingerprint, cookies and JavaScript execution, none of which change with the address class.

A datacenter address can fail the first signal where a target filters on it. An ISP address whose block is held and announced by a consumer provider passes the first signal, the second can still flag it, and the third and fourth apply to both classes equally. So neither class is less detectable in general. What ISP removes is one specific reason for a refusal: being recognized as hosting space. Whether that reason is active on your target, on your flows and at your rate, has to be measured; it can differ between a site's public pages and its sign-in, and change when the site reconfigures its bot management.

Testing both lines on your own target

The test that settles it is small: one address of each line, the same requests, the same pace, interleaved so that time-of-day effects land on both. Our guide to benchmarking proxy providers covers the general method; this is the narrow version for one question.

Prepare three things:

• A URL sample that looks like the job, including any sign-in, search or checkout step production will run. Public listing pages say little about a logged-in flow.
• A content marker: a string found only in a real page, never in a challenge, consent or error page, such as a product attribute or a JSON field name. A 200 status without it is not a success.
• A production pace. A test that runs slower than the real job will pass a target that later rate-limits you.

The script reads each connection string from an environment variable, keeps a cookie session per line as a real client would, alternates which line goes first, and prints a tally per line:

import os
import random
import sys
import time
from collections import Counter

import requests

MARKER = sys.argv[1]
URLS = [line.strip() for line in open(sys.argv[2]) if line.strip()]
PACE_SECONDS = float(os.environ.get("PACE_SECONDS", "5"))
LINES = {"isp": os.environ["ISP_PROXY"], "datacenter": os.environ["DC_PROXY"]}
HEADERS = {
    "User-Agent": "Mozilla/5.0 (X11; Linux x86_64; rv:128.0) Gecko/20100101 Firefox/128.0",
    "Accept-Language": "en-US,en;q=0.9",
}


def classify(response):
    if response.status_code == 429:
        return "rate-limited"
    if response.status_code in (401, 403):
        return "blocked"
    if response.status_code != 200:
        return f"http-{response.status_code}"
    return "content" if MARKER in response.text else "no-marker"


sessions = {}
for line, proxy in LINES.items():
    session = requests.Session()
    session.headers.update(HEADERS)
    session.proxies = {"http": proxy, "https": proxy}
    sessions[line] = session

tally = {line: Counter() for line in LINES}
for url in URLS:
    order = list(LINES)
    random.shuffle(order)
    for line in order:
        try:
            outcome = classify(sessions[line].get(url, timeout=30))
        except requests.RequestException:
            outcome = "error"
        tally[line][outcome] += 1
    time.sleep(PACE_SECONDS)

for line, counts in tally.items():
    total = sum(counts.values())
    print(f"{line:<11} content {counts['content'] / total:.0%}  {dict(counts)}")

Export the two connection strings from the dashboard, then pass the marker and the URL file:

export ISP_PROXY="http://..."
export DC_PROXY="http://..."
PACE_SECONDS=5 python paired_test.py 'data-sku=' urls.txt

Run it more than once and at different times of day. A filter on network class shows from the first requests; a per-address rate limit shows only with sustained volume at the real pace. Open a few no-marker responses before trusting the tally: a changed page template looks like a challenge until you read it.

Reading the result

A result describes that target, at that pace, in that week. Keep the script and the URL sample, and run them again when the target changes or block rates move.

A decision procedure for choosing between them

1. List the hard requirements first. If you must name the consumer ISP at checkout, choose ISP. If an auditor wants ranges whose registry record names the vendor, choose datacenter. If one address must carry more than 100 Mbps, neither line will do it: both run at 100 Mbps per address, so spread the load across more addresses.
2. Run the paired test on the flows the production job will run, at production pace.
3. If both lines pass, choose datacenter. The price and the port speed are the same, so the lower median latency and the one-hour replacement window cost nothing.
4. If only ISP passes, choose ISP. Then size the order from the per-address rate the target tolerates, not from a round number.
5. If both degrade with volume, fix the pace before changing class. More addresses, spread over more /24 blocks, is the remedy for a per-address limit; switching class is not.
6. If neither passes, stop buying static addresses for this job. Price a rotating pool on the per-gigabyte meter instead; proxy pricing per GB vs per IP shows how to put the two meters on one scale.
7. Repeat the test on a schedule. IP-intelligence labels and site rules change, and a pass in one quarter is not a pass in the next.

What you can verify before you commit

A product label is an assertion, and the data that tests it is published by registries and routing projects. Check a sample before you commit to a term or a larger order. Both lines include a paid trial, and the smallest order on either is one address, so the checks can run on a trial allocation or a single address.

The exit address and its network. The proxy checker shows the exit address a target sees, the ASN announcing it and its operator, whether WebRTC exposes a second address, and whether the request carries headers that name a proxy. Its hosting-or-ISP label is a guess from the operator's name, and the page says so. Use it as a first look, then confirm in the registry.

The registry holder and the origin. From a terminal, through the address you are checking:

IP=$(curl -s --proxy "http://HOST:PORT" --proxy-user "$PROXY_USER:$PROXY_PASS" https://api.ipify.org)

curl -sL "https://rdap.arin.net/registry/ip/$IP" \
  | jq -r '.name, (.entities[]? | select(.roles | index("registrant")) | .vcardArray[1][] | select(.[0] == "fn") | .[3])'

ASN=$(curl -s "https://stat.ripe.net/data/network-info/data.json?resource=$IP" | jq -r '.data.asns[0]')
curl -s "https://stat.ripe.net/data/as-overview/data.json?resource=AS$ASN" | jq -r '.data.holder'

The commands print the exit address, the block's name and registrant, and the organization holding the originating AS. ARIN's RDAP service redirects to whichever registry holds the address, so the lookup works worldwide. What to look for:

• On a datacenter address from us: the registrant is us, and the originating AS is ours.
• On an ISP address: there is no single right answer across vendors, because a lease can leave the registration with the ISP or move it, and the route can be originated by the ISP or by the vendor.
• On either: a holder you cannot identify, or output that contradicts what the vendor told you, is a question to settle before you build on the address. A lookup is evidence to weigh, not proof of the product category.

The spread of a batch. Count the distinct /24 blocks across the addresses you receive. ISP batches are capped at 64 addresses per /24 by default, and datacenter spread is configurable on request. The counting script in our static residential proxies guide works on either line.

For the documents behind a registry record, such as ISP lease terms and the sourcing audit, see how to verify a proxy provider's IP sourcing and our sourcing page.

Common mistakes

• Buying ISP by default, to be safe. On a shared rate card the default costs nothing in money and something in performance: a higher median latency and a four-hour replacement window instead of one hour. Buy ISP where the test shows the target needs it.
• Testing a different flow from the one you will run. Public pages and signed-in pages are often protected differently.
• Packing a batch into one /24. A target that limits per block treats the whole batch as one source. Check the spread when the addresses arrive.
• Treating one result as permanent. Classifications move. Re-run the test when the target changes, and before you renew a long term.
• Comparing a shared address with a dedicated one. When you compare vendors, a shared address carries other customers' history, which distorts a test of network class; see dedicated vs shared proxies.

ISP and datacenter proxies at ProxyForge

Our ISP proxies are leased from consumer ISPs and run on our racks; our datacenter proxies come from our own registered ranges and ASN. Both lines are dedicated to one customer, ordered by country from a single address upward, paid per address per month from a prepaid wallet, and include a paid trial before you commit to a term. Both speak HTTP, HTTPS and SOCKS5, so moving a job between them is a parameter change. Point the paired test at your own target and let its result choose the line.