Custom number format for large dollar amounts (positive and negative)

Question

I'm trying to create a custom number format that will display big dollar amounts with the typical k/M suffixes. Examples:

• $1
• $12
• $123
• $1.2k
• $12.3k
• $123k
• $1.2M
• $12.3M

And, actually, I partially managed with the custom number format:

$[>999999]#.#,,\M;$[>999]#.#,\k;$0

My question is how to expand this custom number format to include negative numbers too:

• -$1
• -$12
• -$123
• -$1.2k
• -$12.3k
• -$123k
• -$1.2M
• -$12.3M

I would really like to avoid having to create an auxiliary row or column for this.

Answer 1

Google Sheets doesn't support more than two numeric ranges in a Custom Number Format (as of July 2017).

Therefore, the answer is: not possible without an auxiliary cell.

For my particular case, where I'm displaying dollar amounts, this is the auxiliary cell. Note that it will display $12.3k with one decimal point, but $123k instead of $123.4k. Similarly for negative numbers:

=if(A1 < -1000000, "$" & text(A1 / 1000000, "#.0") & "M", if(A1 < -100000, "$" & text(A1 / 1000, "#") & "k", if(A1 < -1000, "$" & text(A1 / 1000, "#.0") & "k", if(A1 < 1000, "$" & text(A1, "0#"), if(A1 < 10000, "$" & text(A1 / 1000, "#.0") & "k", if(A1 < 1000000, "$" & text(A1 / 1000, "#") & "k", "$" & text(A1 / 1000000, "#.0") & "M"))))))

Almost a duplicate of this other question, as Alex points out.