How Much Did the HP-35 Calculator Cost in 1972?
By the Price Time Machine team · Updated
The HP-35 price was $395 when Hewlett-Packard introduced it in 1972. Adjusted for inflation, that is about $3,183 in September 2026 money, roughly 8.1 times the original price.
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HP-35 Calculator at a glance
- US launch price
- $395
- In today’s money
- ≈ $3,1831972 average (launch month not known) to September 2026 (CPI-U, BLS)
- US launch year
- 1972
- Where the company was based
- Palo Alto, United StatesMade by Hewlett-Packard, whose headquarters were in Palo Alto, California.
- Category
- Gaming & tech
- Price source
- en.wikipedia.org
Today’s price is the US launch price adjusted for US inflation with the Consumer Price Index (CPI-U) from the US Bureau of Labor Statistics, comparing the launch month with the latest published month. It updates automatically as new figures come out.
Why the HP-35 cost $395
The HP-35 was HP’s first pocket calculator and the world’s first scientific pocket calculator. It could do trigonometry and exponential functions, not just add, subtract, multiply and divide.
Before it, slide rules were the only practical portable way to do that kind of maths. Engineers and scientists happily paid $395 to replace them.
The HP-35 price in today’s money
Inflation means a dollar buys less today than it did in 1972. Using the US Consumer Price Index, the original HP-35 price of $395 works out at about $3,183 in September 2026 money, around 8.1 times the original figure. That is what the same amount of spending power would cost now, not what the HP-35 sells for second-hand.
Who invented the HP-35?
In about 1970, HP co-founder Bill Hewlett challenged engineer France Rode to make a “shirt-pocket sized HP-9100”. The HP-9100 was HP’s desktop scientific calculator. Hewlett-Packard was based in Palo Alto, California.
How the HP-35 worked
It used reverse Polish notation (RPN), like the desktop 9100A, instead of typing sums in the usual order. Numbers went on a four-level stack, and you pressed ENTER before choosing an operation.
Its 15-digit red LED display automatically switched to scientific notation for very large or small numbers. It ran on a pack of three rechargeable AA batteries.
When was the HP-35 released?
- Challenge from Bill Hewlett: about 1970
- Introduced: 1972, at $395
- On sale until: 1975
- Named an IEEE Milestone: 2009
HP-35 facts you might not know
- The “35” in its name is the number of keys.
- Its display lit one LED segment at a time, because HP found this looked brighter for the same power.
- In 2007 HP released the retro-styled HP 35s for $59.99 to mark the 35th anniversary.
- It led to a family of HP calculators, including the programmable HP-65.
Frequently asked questions
How much did the HP-35 cost?
The HP-35 cost $395 when Hewlett-Packard introduced it in 1972.
How much is $395 from 1972 worth today?
Adjusted for US inflation, the HP-35’s $395 price is about $3,183 in September 2026 money.
Was the HP-35 the first scientific calculator?
It was the world’s first scientific pocket calculator. HP’s earlier scientific calculator, the 9100A, sat on a desk.
Why is it called the HP-35?
The number 35 comes from the number of keys on the calculator.
Want to compare the HP-35 price with other launch prices? See what the Apple Newton cost, browse more famous launch prices, or play this question in Price Time Machine.
Sources
Launch prices and dates are checked against the sources below. Today’s price is calculated from official US inflation data and updates automatically when new figures are published.