The ability to show the aggregate values of a selection of cells in the result grid was added as part of SQL Prompt 10.15 https://documentation.red-gate.com/sp/release-notes-and-other-versions/sql-prompt-10-15-release-notes.

For reference:
https://www.ssmsboost.com/Features/ssms-add-in-grid-aggregates

Sadly the SSMS Boost product doesnt get upgraded since the founders had a plane accident. As well as I understood at the time. Had been a long term user of SSMS Boost.

any progress on this?

We're now evaluating Red gates Sql Toobelt Essentials and comparing it with Devarts eqvivalent. I would say if Red gata had this feature, then it would be a no brainer to choose between the two. Now Sql complete has this advantage.
Please consider this with a style like sql complete which is very nice.

When we moved to SQL prompt from SQL Complete about a year ago this was a feature that we lost. Team members on our development, support, and DB teams were very upset that there was not way to rapidly sum selected values in a column. It is extremely helpful to be able to do this in SSMS and not have to export results to excel or manually calculate numbers.

I'm a currently a user of sql prompt but I'm looking for a replacement only because you lack this festure. And with ssms boost out of the picture, there's only sql complete left. Please consider this feature in sql prompt!

Please add this feature. Instant purchase for me if added. SQL Complete, SSMS Boost. I prefer the how it is displayed in SQL Complete over SSMS Boost though. It puts an aggregate bar at the bottom of each results grid. You can have aggregates displayed on multiple results grids at the same time this way.

Add the grid aggregates!

Need Results Grid Aggregates Like SSMSboost.
Excel has a perfect function, which allow users to select several cells and see their SUM in the status bar. Well, SSMSBoost adds even more advanced Aggregates functionality to Results Grid:
All you need to do is to select a range of cells. SSMSBoost activates Aggregates windows and starts displaying aggregates. By clicking checkboxes below the calculated results you can select which aggregates to calculate: SUM, MIN, MAX, COUNT, COUNT NULLS, DISTINCT COUNT, AVG.
Please note, that some aggregates are data type-specific and will not be calculated (like there is no SUM for Strings).
Aggregates window, like most of other SSMSBoost windows is dockable floating pane, which can be docked in SSMS environment like any other window. You have to size/dock it when it appears for the first time.
There are some fine-tuning options available under SSMSBoost Settings->Grid Aggregates. Make sure you check them and choose best settings for your usage case.

The SSMSBoost add-on is free, yes. But the "Result Grid Aggregates"-feature is part of the pro-package which costs 150 euro. You can use it for a 30 days trial period.

Source: http://www.ssmsboost.com/VersionCompare

I read the suggestion about SSMSBoost, but it would be nicer to have this functionality in one tool rather than having to install a completely different tool for one piece of functionality. Also, I do not see the correlation between this request and the request for "Recommended Table Structure" suggestion.

Install the free addon http://www.ssmsboost.com/, which will provide you with this informations (in a dockable window).

It works fine with SQL Prompt (but you should disable the snippets in SSMSBoost). Sadly there is no version for SQL2016 or the newest SSMS at the moment.

See "Recommend Table Structure" suggestion. Perhaps the functionality COULD be in SQL Prompt rather than SQL DOC.