The short answer
10 to 15 percent of your gross pay is the common target people use for retirement — and it works. But if 10% is not realistic today, the right number is whatever you can start with and keep up. One percent this year, three next year, five the year after. Starting small and increasing consistently beats aiming for 15% and quitting in three months.
Why most advice on this is unhelpful
Most articles hand you a percentage — "15%!" — as if your budget is a spreadsheet and not a real life with rent, a car payment, kids, and groceries that keep getting more expensive. The problem with the 15% figure is not that it is wrong. It is that when people cannot hit it, they hit zero instead. Perfect becomes the enemy of any.
At the same time, the "just invest whatever you can" answer is too soft. Without a target, most people drift at 2% forever and wonder why the account looks small at age 55. The real framework needs two things: a realistic starting point and a mechanism to grow it.
The math that actually matters
Imagine you earn $55,000 a year — roughly $2,100 every two weeks before taxes. Ten percent is $210 per paycheck, or about $5,500 a year.
At a 7% average annual return, that $5,500 a year over 30 years grows to roughly $520,000. That is without any raises, without any employer match, without doing anything fancy. Just the same amount, every paycheck, for three decades.
Now adjust. If you can only do 5% — $2,750 a year — that same 30 years gets you around $260,000. Half as much, which tracks.
But here is the part nobody mentions. If you start at 3% and bump it up by 1% every time you get a raise over ten years, you land at 13% — without ever feeling the jump. Raises are the easiest place to squeeze more in, because the extra money has not yet become "yours" in your head. You do not miss what you never saw.
If your employer offers a 401(k) match, that is not optional math. A 50% match on the first 6% of your contributions is an instant 50% return on that money — before it has done anything in the market. That is free payroll. Not capturing it is leaving actual cash on the floor every pay period.
Your specific situation matters
Places where the number shifts:
If you are carrying high-interest debt (credit cards over 15%), your first "investment" is the debt, and your second is the 401(k) match. Do that much. Do not try to also hit a 15% market contribution if the credit card is on fire.
If your income is volatile — overtime, shift work, commission, contracting — pick a conservative base percentage off your reliable income, then do a year-end sweep of a portion of any windfall (bonus, tax refund, heavy OT year). This keeps your commitments realistic but captures the good years.
If you are in your 50s and started late, the 15% target is not aggressive enough. You probably need 20-25% for the next decade-plus to reasonably catch up. That is a hard conversation with your budget, but pretending otherwise is worse.
If you are in your 20s and every dollar counts, 5% is a perfectly respectable start, especially if you get an employer match that pushes the effective total to 8-10%. Time is on your side — compounding does more work the earlier it starts.
What I would actually do if I were starting over
First paycheck, I would go into HR or payroll and set up a 401(k) contribution at whatever percentage captures the full employer match. If my employer matches 50% of the first 6%, I contribute 6%. That is non-negotiable. Free money does not come twice.
Then I would set up a second automatic transfer from my checking account to a brokerage account on payday, before I can see the money sitting there. Even if it is only $25 a check. The point is to build a second lever I can crank up later when my income grows.
Every time I got a raise, I would increase the 401(k) by 1 percentage point and bump the brokerage transfer by $25. Every time. No exceptions. Within five or six years, I would quietly be a double-digit-percent investor without ever having a "tighten the belt" conversation with myself.
When bonuses, tax refunds, or big overtime checks landed, I would throw a chunk into the brokerage. Not all of it — life is for living, too — but a consistent portion.
Common mistakes
Mistake one: picking a percentage so high you bail on it in three months. A 1% habit that lasts forever beats a 15% attempt that lasts one quarter.
Mistake two: skipping the employer match. I have said it twice and I will say it again because people leave tens of thousands of dollars on the table over a career. Capture the match first. Everything else comes after.
Mistake three: treating investing as the last thing in your budget. If "whatever is left over" is the plan, the answer at the end of the month is almost always zero. Investing has to be automated and pulled out before your brain sees the money — otherwise it gets spent, and you think you cannot afford to invest. You can. Your brain just got there first.
The bottom line
10-15% of gross pay is the target. 1% starting today is a better first step than 15% someday. Capture every dollar of employer match, automate everything, and ratchet the percentage up with every raise.