I wouldn't necessarily add a dollar value, but a %. For example, a 1099 IC is responsible for the both the employer and employee portion of Social Security (6.2% x 2) and Medicare (1.45% x 2) tax. Or, an additional 7.65% the employer would pay as W2 employee. As a W2 employee, you must evaluate your benefits package; health insurance, 401k including any employer match, paid time off (PTO), any employer paid malpractice ins, licenses, association dues.
As a 1099 IC you're considered a business, therefore you can deduct business expenses; associate dues, professional licenses, continuing education, malpractice insurance, health insurance premiums, dental equipment, lab fees if you pay for them, conference fees, business travel and a few others. And as mentioned, you can contribute to a solo/individual 401k with contribution limit (~$62K of 2023) and also to a Health Savings Account (HSA) of up to ~$3,750 for single if you have a qualified high deductible health insurance plan. Contribution for 401k and an HSA lower your taxable income.
Ballparking, I would expect the 1099 IC compensation to be about 10% to 15% greater than the W2 position. Good luck!