Why does Class A cost roughly twice as much as Class C

Scarcity, and nothing else. There is no additional feature attached to a Class A address, no faster route, no better hardware. The difference in price tracks the difference in how many of each exist, and the gap in supply is not small: the entire IPv4 address space contains a couple of hundred first-octet ranges, against millions of third-octet blocks.

How the supply actually breaks down

The first octet of an IPv4 address has a limited set of usable values, and those ranges were allocated early. Universities, governments and a handful of corporations received them when the address space felt infinite, and most have never been returned. Nothing new is being created. Whatever exists is what will ever exist.

Third-octet blocks are a different world. They are carved out of larger allocations continuously, and any provider of size holds many. That is why a Class C order can run to hundreds of addresses while a Class A order is limited to a handful per region, and it is why the two cannot be priced alike.

Why that translates into rate rather than availability

A provider with a fixed, non-renewable stock of something has two options: ration it by queue or ration it by price. Rationing by queue means telling customers to wait for stock that will never arrive. Rationing by price means the addresses go to the people for whom the separation is genuinely worth it. The second is the only one that works.

The practical effect is that Class A sells in small quantities to buyers with a specific reason, rather than in bulk to anyone comparing per-address rates. That is the intended outcome.

Is the premium worth paying

Sometimes, for a small part of an estate. The honest framing is that you are not buying performance and you are not buying a ranking effect. You are buying the widest separation that can be bought, for the properties where the cost of being associated with the rest of your estate would be high.

For the other ninety percent of a typical network it is poor value, and we would rather say so. Third-octet diversity already removes the pattern that a casual check would find. Paying several times over for the remaining margin, across every site you own, spends money that would do more work on content or on registrar and template variation.

A reasonable way to decide

• List the properties where association with the rest of the estate would cause real damage. Keep the list short and honest.
• Give those the widest tier your budget supports.
• Give everything else third-octet diversity.
• Spend the difference on the non-technical footprints, which no tier addresses.

Current rates for each tier live on the product pages: Class A hosting, Class B hosting and Class C hosting. The regional address counts sit in IP Diversity. IANA publishes the current state of the address space in its IPv4 registry if you want to see the allocation for yourself.