Hello, @SidMerrett-4938!

A quick disclaimer before I try to answer your question: For questions about billing you'll want to reach out to billing directly as we're set up to answer questions of a more technical nature. You can do this by opening a billing ticket in the portal by going to Help + support > New support request > Billing and then completing the wizard.

Am I the only one seeing this?
I'm seeing the same prices you are from the Azure Pricing Calculator. No need to troubleshoot your browser or session. See more on exactly what I'm seeing below.

Making a comparison
Before getting into the pricing calculator, it may be helpful to use the pricing options guide when comparing the cost of several different VM SKUs or benefit price vs reserved price:

https://azure.microsoft.com/en-us/pricing/details/virtual-machines/sql-server-standard/

Example 1: The Bs Series
I went through the Bs-series with the following configuration:

Region: UK South
OS: Windows
Type: SQL Server
Tier: Standard
License: SQL Standard

Compute / OS (Windows) / Software (SQL Server)

B1ms (1 core ) : £12.73 / £2.16 / £215.74
B2ms (2 cores): £50.91 / £4.10 / £215.74
B4ms (4 cores): £101.94 / £8.63 / £215.74
B8ms (8 cores): £203.87 / £17.26 / £431.47
B12ms (12 cores): £305.27 / £25.89 / £647.21
B16ms (16 cores): £407.20 / £34.52 / £862.95
B20ms (20 cores): £509.14 / £43.15 / £1,078.68

At least for this example we see a relatively linear increase in OS cost that corresponds to the number of cores (at a little over £2 per core). For the software cost, it appears that there is a minimum cost up until 4 cores and then a linear increase of roughly £215.74 for every 4 cores added.

Example 2: DS SKUs
I went through the DS SKUs with the following configuration:

Region: UK South
OS: Windows
Type: SQL Server
Tier: Standard
License: SQL Standard

Compute / OS (Windows) / Software (SQL Server)

DS14-4 v2 (4 cores) : £1,010.73 / £316.05 / £215.74
DS14-8 v2 (8 cores) : £1,010.73 / £316.05 / £431.47
DS12 v2 (4 cores) : £252.95 / £78.74 / £215.74
DS13 v2 (8 cores) : £505.36 / £158.03 / £431.47
DS14 v2 (16 cores) : £1,010.73 / £316.05 / £862.95
DS15 v2 (20 cores) : £1,263.68 / £394.80 / £1,078.68

Here, having the DS14-4/8 v2 along side the DS12-15 v2 lineup helps make things clearer. You can see that both the DS14-4 v2 and DS14-8 v2 have the same OS cost as the DS14 v2 (£316.05) while the software cost matches the core count (£215.74 and £431.47). Looking at the DSv12-15 v2 you can see the same linear increase in OS and software cost.

Hi - thanks for the input.
Are you echoing my confusion or attempting to explain the anomalies though?

As far as I can see, your numbers confirm that there is a fundamentally indecipherable relationship between the cost of the OS and SQL licenses and the CPU count of a given VM model and series in Azure.

That is based on these principals: SQL Server is priced per 2 core "pack" and Windows Server OS in packs of 8 cores and and CPU performance is not relevant to license cost.

So the OS price varies wildly per-CPU based on VM series (i.e. performance). Why?
SQL Server is consistently priced per CPU core, except when there are only 2 cores. In which case, you pay for 4 core licenses. Why?

The key difficulty I am facing, is trying to put together real-world price comparisons between Reserved Instances, subscription (e.g. EA) SQL and OS licenses and PAYG equivalents.
Made difficult because Microsoft uses an unknown/unpublished pricing model on PAYG, for software licensing.

One other observation : Pricing of the virtual hardware (compute) is also strange in some series (of course it is the absolute discretion of the vendor, but why the inconsistency?)
For example, the DS14_V2 series 4, 8 and even 16 CPU machines are all priced the same for compute.
So you can have a 4, 8 or even 16 CPU core, 112Gb RAM VM for £1,010.73 per month compute on PAYG, in UK West.

?