How Much Work Does That Purchase Really Cost?

Have you ever wanted the new iPhone and immediately checked your savings account to decide whether to buy it?

In my opinion, that’s the wrong place to start. Your savings are part of your net worth, and they’re hard enough to build when everyday life costs so much. Before I spend, I want to know how much longer I’ll have to work to save that money again.

Apple’s new foldable iPhone Duo starts at $1,999.¹ Say you save $1,000 a month after paying rent, buying food, and covering your other bills. At that rate, it takes about two months of work to put the $1,999 back into your savings.

I started thinking about purchases this way during my 16 years in corporate jobs. It took me longer to notice what those working hours were costing me outside the office.

How to calculate how much your time is worth

Start with what you save in a typical month, after rent, food, commuting, and other regular bills. That amount determines how long it will take to save the money again after a big purchase.

To express the cost in hours, first work out how much you save per hour. Divide your monthly savings by 170, a rough estimate of the hours in a month of full-time work. Use your own working hours if they differ.

The less you save each month, the longer it takes to put that $1,999 back:

How I used it before a big purchase

I use this most often when planning a trip home to see my parents in India. When I was earning a salary, I kept the trip and that month’s regular bills within one month of take-home pay. I covered rent, food, and commuting first. The most I would spend on the trip was what I could otherwise have saved that month.

I could save money by skipping the trip, but then I’d miss that time with my parents. Alongside the work it takes to pay for the trip, I think about the days I’ll get with them.

I want my net worth to keep growing, so I set a spending limit before I start shopping.

Some expenses are out of your control. When our kitten Chandi needed emergency vet care, we used our emergency fund. The same calculation tells you roughly how long it will take to rebuild the fund after a vet bill, car repair, or dental bill.

I tracked my spending closely and usually spent much less than my limit. Choose your own limit, and don’t let other people’s expectations set it.

The three months’ salary engagement ring rule, measured in savings

The idea that an engagement ring should cost months of pay came from a De Beers ad² in the 1980s. My wife and I never followed that rule.

Say you spend three months of take-home pay on a ring and normally save 20% of your take-home pay each month. At that rate, it would take 15 months of work to save the money again: three divided by 0.20.

Is an engagement ring worth more than a year of hustling? For some people, maybe. But if you’re trying to build financial security, it’s a tradeoff worth thinking through.

The hours a paycheck doesn’t show

The cost of a purchase is fairly easy to measure this way. It’s harder to see what you miss while you’re working to pay for it.

Product launches and deadlines pushed some of my workweeks well past 40 hours, sometimes spilling into weekends spent answering work emails. I chose many of those extra hours. Early on, I wanted to stand out among my peers. Later, I wanted to get better at the work itself. As a leader, that also meant learning enough to make good decisions. Raises and promotions kept me pushing.

Those extra hours mostly came out of my weekends, leaving less time for family and friends, trying new food, being outdoors, or going to a movie.

When a deadline is close, it’s easy to say, “Let’s do it next weekend.”

In my twenties, I didn’t think about how much harder it would become to find time together. My friends were building careers and taking on other commitments too. Finding a time when everyone is free can feel like finding a unicorn. Things we once did without planning now happen once every few months, or even years.

How much time do you have left with your parents?

Moving away for work adds another cost. Many people move to another city or country, and some go years without seeing their parents. Say you’re 30 and your parents live for another 30 years. If you visit them once a year for two weeks, that adds up to 420 days together.

I live in the US, and my parents live in India. Over the last ten years, I’ve spent about 150 days with them, an average of 15 days a year. Work is optional for me now, but we still live just as far apart. I can’t simply visit more often, though I plan to go every year. A move for work can shape your life long after you leave the job.

These are sacrifices most of us make as adults, often without noticing. Protect your personal time where you can. Early in your career, you may have less say over your hours, and saying no can feel risky when you’re trying to prove yourself.

Start with what you can control, even if that’s protecting one planned evening with friends. Enjoy that time without guilt.

Is trading time for money worth it?

For me, it was. My career helped me build the financial security that later made work optional. I also met colleagues whose ideas changed how I think about life, money, and work. Without the mentors I met along the way, I probably wouldn’t have taken the leap.

I’ve never turned down a job because of the hours. Sometimes the opportunity makes those long hours worth it.

I still find it hard to weigh the money I earn against the time I give up. But I’m more aware now that life is short, so I make a point of talking to the people I love and spending time with them. I also make time for work I enjoy. Right now, that’s building new things and learning to work with AI.

Look at the time a choice will cost you alongside the money. Then decide.