Texas Instruments TI-81 Graphing calculator

General specifications
Type Graphing calculator
Production years 1990 - -
New price USD 110
Operating system n.a.
Chipset/CPU ZiLOG Z80 @ 2 MHz
I/O none
Performance index 0
Entry method Formula entry
Precision 13 digits
Advanced functions

Forensic result 8.999999616566

Graphing calculator: Texas Instruments TI-81
Programming model Formula programming
Programming features

Program display Formula
Program editing Formula entry
Programming 2400 bytes
Data 2400 bytes
Type LCD
Size 9664 pixels
LWH 1528912 mm
Weight 280 g
Batteries 4AAA + 1CR-2016
External power -
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The TI-81, TI's first graphing calculator, was designed for algebra and precalculus. It has since been replaced by newer models which have faster processors, more memory, and popular features such as linking capability and flash upgradability. The TI-81 drew little in the way of third-party games and other programs, since the code must be typed into the calculator by hand.

Undocumented features

From time to time, TI will update the internal code of their calculators to work around bugs, optimize functions, and even add features. This results in several versions of each calculator in the marketplace. You can check the ROM version of your TI-81 using the following key sequence and reading the number on your screen:


After entering the above key sequence, DO NOT PRESS ENTER! If you do, your calculator's memory will be erased during the self-test sequence. Press any other key to exit back harmlessly.

Known ROM versions: 1.1, 1.6K, 2.0


Graphing calculator: Texas Instruments TI-81

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This page was last modified on October 4th, 2008

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3 Responses so far

is there any software on the market that would allow me to do the same graphing on my laptop as i can do on my ti-81 only i would be able to print results for my studies.
fintan m. smyth
fintan m. smyth
January 14th, 2010
Hi bk,

I think you'll need to start looking for a new calculator, the TI-81 doesn't support complex arithmetics.
May 14th, 2009
how do you use this for compelx fracionns
May 11th, 2009