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HP-45

The HP-45 is the second scientific pocket calculator introduced by Hewlett-Packard, adding to the features of the HP-35. It was introduced in 1973 with an MSRP of US$395 (equivalent to $2,865 in 2025). Especially noteworthy was its pioneering addition of a shift key that gave other keys alternate functions.

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Dimensions
Length: 5.8 inches (150 mm), width: 3.2 inches (81 mm), height: 0.7–1.3 inches (18–33 mm)
Discontinued
1976
Display size
15 digits (decimal point uses one digit), (±10±99)
Display type
Red LED seven-segment display
Entry mode
RPN
Introduced
1973

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Emulators

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HP-45

Nodes20
Edges19
Triples12
Avg. degree1.9
Density0.1
Components1

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HP-45

Top relations

Dimensions · 1
HP-45 → Length: 5.8 inches (150 mm), width: 3.2 inches (81 mm), height: 0.7–1.3 inches (18–33 mm)
Discontinued · 1
HP-45 → 1976
Display size · 1
HP-45 → 15 digits (decimal point uses one digit), (±10±99)
Display type · 1
HP-45 → Red LED seven-segment display
Entry mode · 1
HP-45 → RPN
Introduced · 1
HP-45 → 1973
Memory register · 1
HP-45 → Four-register operational stack with nine addressable memory registers + LASTx register
Power supply · 1
HP-45 → Internal rechargeable battery or 115/230 V AC, 5 W
Programming language(s) · 1
HP-45 → RPN key stroke
Type · 1
HP-45 → Scientific

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Important terminology

calculator introduced mode stopwatch key us second accurate scientific pocket display emulators hewlett-packard hp-35 msrp hp-55 calculators adding features 1973

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
HP-45DimensionsLength: 5.8 inches (150 mm), width: 3.2 inches (81 mm), height: 0.7–1.3 inches (18–33 mm)1.00infobox
HP-45Discontinued19761.00infobox
HP-45Display size15 digits (decimal point uses one digit), (±10±99)1.00infobox
HP-45Display typeRed LED seven-segment display1.00infobox
HP-45Entry modeRPN1.00infobox
HP-45Introduced19731.00infobox
HP-45Memory registerFour-register operational stack with nine addressable memory registers + LASTx register1.00infobox
HP-45Power supplyInternal rechargeable battery or 115/230 V AC, 5 W1.00infobox
HP-45Programming language(s)RPN key stroke1.00infobox
HP-45TypeScientific1.00infobox
HP-45WeightCalculator: 9 oz (260 g), recharger: 5 oz (140 g)1.00infobox
HP-45is asecond scientific pocket calculator introduced by Hewlett-Packard0.90text

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