confession: i’m asian and i can’t do mental arithmetic .. thus an app?

When I do maths in my head, I round. Aggressively. Anything beyond the basics and my 8 brain cells go on strike.

Which is fine when you’re splitting a bill at home, but not when you’re travelling in Korea or Japan, where the numbers look like someone sat on the zero key.

A bowl of ramen? ¥1,200.

A taxi ride? ₩24,000.

My coping mechanism was simple: just drop the last two or three digits and call it close enough.

Which meant I was basically giving myself a 10–20% discount on everything. Fantastic for my feelings, terrible for my bank account.

Then I travelled to Europe and the US and ran into the opposite problem. Suddenly everything looked too cheap.

A €2 espresso?

A $5 sandwich?

Bargain! Except… not really. Because $1 ≠ $1 once you convert it.

Psychologists even have a name for this: money illusion. Our brains see a small number and forget it’s secretly bigger in another currency.

My budget said, “please stop,” but my brain said, “don’t worry, it’s just a couple of bucks.”

Spoiler: the budget was right.

And that’s just the spending while travelling.

Currently I am ‘planning’ for a japan trip and before my latest Japan trip even began, I was already in financial chaos.

Cruise booked in TWD through a Taiwanese agency, flights in AUD, hotels in JPY.

I hadn’t even packed my suitcase and I’d already lost track of how much I’d spent.

1. Big Numbers, Small Brain

Here’s the thing: the human brain hates big numbers. And mine especially. Research shows that once digits climb too high, we instinctively round down and underestimate. Which is fine if you’re estimating sheep in a paddock, but not when you’re trying to figure out whether that ramen was $12 or $18 back home.

That’s why currencies like yen and won break me. You’re constantly juggling thousands. ¥1,200 for ramen. ₩24,000 for a taxi. It doesn’t matter what the actual rate is — my brain quietly drops a zero, maybe two, just to cope.

Which means on paper, I’m underspending like a budgeting queen. In reality, my credit card statement looks like a crime scene.

The math doesn’t math, and the joke is on me.

2. Cheap Thrills, Hidden Costs

Then there’s the sneaky opposite problem: currencies that look deceptively tiny. Europe, the US — the numbers feel harmless. “It’s only €10.” “It’s just five bucks.” Except when you check your statement later, it’s $17 AUD here, $9 AUD there, and suddenly you’ve dropped half your grocery budget on “cheap” coffee.

This is the money illusion in action. Economists have studied it for decades — when numbers look small, people spend more freely. And it works.

My brain loves the illusion.

My budget does not.

Pile on conversion fees, booking in multiple currencies, and America’s habit of sneakily adding tax at the till (looking directly at you, New York bagel), and you’ve already lost track before you even board the plane.

I hadn’t even left Brisbane and my budget was already gaslighting me.

3. Clarity on the Road

That’s when I thought: surely this can be simpler. Because honestly, who wants to math on holiday? You’re supposed to be sipping coffee in a piazza, not calculating if it’s €2.50 or $4.17 plus fees.

The problem was, every app I found was built for splitting costs with friends. And I’m a solo traveller.

I have no one to split with ( tragic but true).

What I needed was something that worked the way I travel: offline when I’m on a plane, easy enough to dump numbers in without thinking too hard, smart enough to juggle multiple currencies but still show me the total in one.

And, because I’m a sucker for aesthetics, I wanted it to feel analogue — more like a retro travel diary than a corporate finance dashboard.

So yes, I built minimally travel. Not to scream about exchange rates, but to give me peace of mind that I wasn’t quietly haemorrhaging yen, euros, and dollars just because rounding is my coping mechanism.

Conclusion: Why I Built It

minimally travel didn’t start as some grand fintech vision.

It started with me, standing in a konbini in Tokyo, rounding down onigiri prices like a clown.

It started with me booking a cruise in TWD, hotels in JPY, flights in AUD, and losing track before I even left home.

I don’t like the feeling of not knowing what I’m spending.

I don’t like pretending $1 = $1 when it doesn’t.

And I definitely don’t like finding out weeks later that my “cheap trip” cost double what I thought.

So yes, being the spirally, overly-enthusiastic app stan I am, I decided: if there’s a simple need, there should be a simple solution. minimally travel is my answer — part diary, part offline calculator, all retro vibes.

Because if my brain insists on rounding, at least my app won’t.