The best way to figure it out is to use the IRS calculator or follow all the instructions and worksheets on the W-4, not just the front page. You do one calculation to set the withholding for both spouses.
Assuming your income, deductions, credits and dependents will be similar for 2023, you could also just arrange to have an extra $13,000 withheld from one or both paychecks (using form W-4 box 4C). Assuming that request could take effect with your employer on May 1, you would need to have an extra $1625 withheld per month from one job ($1625 per month, or $813 per check if paid semi-monthly, or $684 per check if paid bi-weekly, or $342 per check if paid weekly). You could lower that amount on 1/1/24 since you would be spreading the $13K out over 12 months instead of 8 months. I suspect the IRS calculator will come up with a similar answer.
