Looking on the internet deeply has found these results:

Can you please let me know is the most popular phrase on the web.

Could you please let me know 11,450,000 results on the web	Can you please let me know 18,080,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
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Could you please let me know

11,450,000 results on the web

Can you please let me know

18,080,000 results on the web

More popular!

Please let me know as quickly as you can.
Okay. Please let me know.
Please let me know as soon as you have learned what has happened.
Please let me know what you want.
If you've figured out how to achieve serenity in face of certain death, would you please let me know.
If you plan to make anything disappear... please let me know.
So will you please let me know...
If I can help with anything please let me know.

Please let me know what you want.
Can you please just let me know that you're okay?
If I can help with anything please let me know.
So will you please let me know...
If you plan to make anything disappear... please let me know.
Please let me know as soon as you have learned what has happened.
If she does get in contact with you, can you please let me know?
If you've figured out how to achieve serenity in face of certain death, would you please let me know.