When backup / restore will finish (ETA) in SQL server

You can use below query

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SELECT r.session_id,
r.command,
CONVERT(NUMERIC(6,2),r.percent_complete) AS [Percent Complete],
CONVERT(VARCHAR(20),DATEADD(ms,r.estimated_completion_time,
GETDATE()),20) AS [ETA Completion Time],
CONVERT(NUMERIC(10,2),r.total_elapsed_time/1000.0/60.0) AS [Elapsed Min],
CONVERT(NUMERIC(10,2),r.estimated_completion_time/1000.0/60.0) AS [ETA Min],
CONVERT(NUMERIC(10,2),r.estimated_completion_time/1000.0/60.0/60.0) AS [ETA Hours],
CONVERT(VARCHAR(1000),(SELECT SUBSTRING(text,r.statement_start_offset/2,
CASE WHEN r.statement_end_offset = -1
THEN 1000
ELSE (r.statement_end_offset-r.statement_start_offset)/2 END)
FROM sys.dm_exec_sql_text(sql_handle)))
FROM sys.dm_exec_requests r WHERE command IN ('RESTORE DATABASE','BACKUP DATABASE')
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