How to Store Variables on the TI-84 Evo

The TI-84 Evo can save a number into a letter, A through Z, and reuse it in later calculations. The key that does it is sto→, down in the bottom-left corner above on.

Store a value in a variable

  1. Type the number you want to save, for example 5.
  2. Press sto→. It drops a → arrow in after your number.
    TI-84 Evo keyboard with the sto key highlighted in the bottom-left corner
  3. Press alpha, then a letter key. Letters are the green labels above the keys. A is the green letter above math, so press alpha then math and the line reads 5→A.
    TI-84 Evo keyboard with the alpha key and the math key highlighted, showing the green letters above the keys
    The TI-84 Evo home screen showing 5 arrow A on the entry line
  4. Press enter. The 5 is now stored in A, and the calculator echoes it back on the right.
    The TI-84 Evo showing 5 stored into A, with 5 returned on the right

Don't skip that alpha press. The letter keys type numbers and menus until you hit alpha first, so pressing math straight after sto→ just opens the MATH menu instead of typing A.

Recall it and use it

Once a value is stored, type the letter anywhere you would type a number: press alpha then the letter, and the calculator uses whatever you saved.

  • Type A on its own and press enter to read the value back: 5.
  • Drop A into an expression like A+10 and it computes with the stored value: 15.
The TI-84 Evo showing A equals 5 and A plus 10 equals 15

Storing a new number into the same letter overwrites the old one, so A stays 5 until you replace it.

Good to know

  • X skips the alpha step. The X,T,θ,n key (just right of alpha) types X on its own, since X is the variable graphs use. Handy when you're storing something you'll graph later.
  • 2nd then sto→ is Rcl. Instead of referencing a letter live, Rcl pastes its stored value onto the entry line so you can edit it. Press 2nd, sto→, then the letter, and enter.
    The TI-84 Evo showing the Rcl A prompt at the bottom of the screen
  • Any letter from A to Z works, plus θ. Pick one you'll remember.
  • Stored values stick around. A variable keeps its value until you overwrite it or clear the calculator's memory, so what you set today is still there tomorrow. Resetting the RAM wipes them all back to zero.