Best Method to Delete 12M rows from SQL table

Question

I have a table currently with 100M+ rows of telemetry data. The table often receives duplicate records.

I can identify duplicate records using a row_number() partition and estimate there are approximately 12M duplicate rows.

What is the option to delete the 12M rows?

• Insert non-duplicates into a new table and drop existing table, recreate indexes?
• Using a join to delete the duplicates?
• Delete in batches? What size?
• Do I drop indexes first?

There are no production requirements to keep the db online.

Thanks for your help.