i7 and i5 are just "market segment" identifiers. Even in the first few generations, there were "i7" cpus that were inferior to "i5" ones.

In general, you can only infer very little from the marketing names. To have any actual idea, you have to look at benchmarks. In practice, 13600 is ~70% faster per thread, and has 2.5 times the threads.

Intel’s naming convention on consumer parts is relatively easy to grok, as it’s been much more consistent for the last 12 years than their server/workstation parts.

Breaking both down we have 3 things to take note of:

i5/i7 - indicates relative performance or feature set within a given generation, bigger is generally better

13/7 - the generation of processor

600/700 - where Intel rates a given processor within a generation, this is consistent and doesn’t (to my knowledge) involve overlap between i3/5/7/9 - generally bigger is better.

So i5-13600 is a thirteenth gen i5, type 600. i7-7700 is a seventh gen i7, type 700

Then you get the legion of letter suffixes determining other features, mobile SKUs etc.

Also, “gens” are announcing/releasing during every year, starting 2010, so 7700 was released in 2016 and 13600 at the end of last year. Performance gains are shifting unevenly sometimes there is marginal gains, sometimes (when AMD bites) it is much more. For example i7 2017 is equivalent of i3 from 2020.

7700 is 7th generation, 13600 is 13th generation, so they are about 6 years apart. The 600 and 700 tells you something about how they are positioned within their generation (bigger equals better). i5 vs i7 is a difficult topic. i7 generally has more hardware features enabled and has the higher end models. But unless you want specific features it's not so big of a deal.

Looking up the numbers instead of reading them like tarot cards, I can tell you that the i7 7700 is a 8 core processor with a max turbo frequency of 4.20 GHz, and the i5 13600 is a 14 core with 6 cores that can do 5 GHz, and 8 efficiency cores capped at 3.7GHz. And both support VT-d, which is about the only feature I would care about :D

Recently, and especially with this gen, the line between i5 and i7 is coming down to the amount of cores itself not the single core peformance. Basically 14 Cores, 20 Threads @3.5GHz vs 16 Cores, 24 Threads @3.4GHz.

What used to be the i7 was (like with the i7-7700) now occupied by the i9 line

The value price of the 12600k is just much better

Which i7?

I like to use Passmark as a very rough comparison for CPUs. Emphasis on rough, but probably grounded in reality. Whether the user can utilize such performance, or if they have a specific workload that isn't ideally multithreaded, is critical.

i5-13600k is around 38000 points (https://www.cpubenchmark.net/cpu.php?cpu=Intel+Core+i5-13600...)

i7-7700k is around 9600 points (https://www.cpubenchmark.net/cpu.php?cpu=Intel+Core+i7-7700K...)

So the new i5 is nearly 4x faster than the old i7. New CPUs have come a long way over the last few years.

Some of this is additional cores (4x overall). On a single thread, the 13th gen is only about 50% faster than 7th (2727 to 4190).