T1 84 Calculator
A free TI-84-style calculator that runs right in your browser. Three modes cover the work students actually do: a scientific mode with trig, logs and combinatorics, a graphing mode that plots up to three functions with trace and zoom, and a statistics mode with 1-variable summaries and least-squares regression. No download, no signup, nothing leaves your device.
T1-84 Calculator (TI-84 Style)
Scientific, graphing and statistics modes in your browser. Not affiliated with Texas Instruments.
Quick Answer
How to use the three modes
Pick a tab, fill in the inputs, and press Calculate. Nothing computes until you do: every results box stays hidden until you ask for it.
Scientific mode
Type an expression into the box or tap the keypad, then press Calculate (or Enter). Functions need parentheses: sin(30), nCr(5,2), sqrt(144). The angle mode starts in radians, exactly like a real TI-84; the RAD button toggles to degrees and stays visible so you always know which mode is active. ANS recalls your last answer, and every calculation is kept in a short tap-to-reuse history of the last eight results. Multiplication can be implicit: 2(3+4) evaluates to 14 without a multiplication sign.
Graphing mode
Enter up to three functions as Y1, Y2 and Y3 using x as the variable, for example x^2, 2*x+1 or sin(x). Set the viewing window with Xmin, Xmax, Ymin and Ymax, then press Graph. The tool samples each function 400 times and reports what it found, for example Y1 = x^2: 401 points, y in [0, 100]. Hover or tap the graph to trace exact values on every plotted curve. Zoom in and Zoom out rescale the window around its center; Standard window restores −10 to 10 on both axes. Clear empties the functions, while Reset restores the x^2 worked example.
Statistics mode
Choose 1-variable and paste one list of numbers (commas, spaces or line breaks all work) to get count, mean, sample and population standard deviation, min, quartiles, median, max and the sums. Choose 2-variable and enter one x, y pair per line, for example 1,2 on the first line and 2,3 on the next, to get the same summaries on each variable plus the least-squares regression line y = ax + b, the correlation coefficient r and r². If every x value is identical, the slope cannot be computed and the tool says so plainly instead of inventing a number.
The formulas and defaults this tool uses
The scientific mode evaluates your expression with a real parser, not a shortcut. It tokenizes the input, inserts implicit multiplication, then evaluates with correct precedence: parentheses first, then factorials, powers (right-associative, so 2^3^2 = 512), unary signs, multiplication and division, and finally addition and subtraction.
| Group | Supported input |
|---|---|
| Trigonometry | sin, cos, tan, asin, acos, atan, sinh, cosh, tanh |
| Logs and powers | ln, log (base 10), sqrt, cbrt, exp (e^x), 10^x, x^2, x^y |
| Combinatorics | n! (factorial, whole numbers 0 to 170), nCr, nPr |
| Rounding and misc | abs, floor, ceil, round, min(a,b), max(a,b) |
| Constants and memory | π, e, ANS (last answer) |
Three defaults are worth knowing before you type. First, angles are radians unless you tap the RAD button, which is the TI-84 behavior; sin(30) in radians is −0.9880316241, while sin(30) in degrees is exactly 0.5. Second, the display rounds every result to 10 significant digits, so 0.1+0.2 shows as 0.3 instead of the raw floating-point artifact; very large or tiny results switch to scientific notation, like 1.000000e+13. Third, graphing always uses radians even when the scientific mode is in degrees, because the window math has no angle toggle; to graph in degrees, scale the input yourself with x*π/180.
Errors are specific instead of cryptic. Division by zero, the square root of a negative number, and tan(90°) in degrees each get their own message. Factorials stop at 170 with a Factorial overflow note. One honest quirk: cbrt of a negative number errors out (“Result is not a real number”) because the engine computes it as a fractional power; a future version could return −3, but today it will not pretend.
The statistics mode uses the textbook formulas. For 1-variable data it reports n, the mean, the sample standard deviation Sx and the population standard deviation σx, the five-number summary, and Σx and Σx². Quartiles use linear interpolation between the closest ranks, which is the same method Microsoft Excel uses for its percentile function. If you want a deeper regression workout with more explanation, the linear regression calculator page covers the same least-squares math in more depth, and the statistics calculator page handles general descriptive stats. For 2-variable data the tool fits the least-squares line y = ax + b, which minimizes the sum of squared vertical distances, with a = [nΣxy − ΣxΣy] / [nΣx² − (Σx)²], b = ȳ − a·x̄, and r measuring how tightly the points follow a straight line on a −1 to 1 scale.
Worked examples, checked against this exact tool
Every number below was produced by the calculator on this page, not copied from a manual.
Example 1, scientific. The expression box starts with nCr(5,2). Press Calculate: the tool reports 10, the number of ways to choose 2 items from 5. Switch to DEG with the RAD button, clear the box, and enter sin(30) for exactly 0.5; type 5! for 120.
Example 2, graphing. Y1 starts with x^2 and the standard −10 to 10 window. Press Graph: the info line reads Y1 = x^2: 401 points, y in [0, 100]. Hover near x = 3 and the trace shows Y1 = 9. Add Y2 = 2*x+1 and you will see the straight line cross the parabola exactly where the algebra says it should.
Example 3, statistics. The data box starts with 2, 4, 4, 4, 5, 5, 7, 9. Press Calculate: n = 8, mean = 5, Sx = 2.138089935, σx = 2, min = 2, Q1 = 4, median = 4.5, Q3 = 5.5, max = 9, Σx = 40, Σx² = 232. Switch to 2-variable and enter the pairs 1,2 / 2,3 / 3,5 / 4,4 / 5,6 (one pair per line): the tool returns the regression line y = 0.9x + 1.3 with r = 0.9 and r² = 0.81.
| Check | Input | What the tool returns |
|---|---|---|
| Implicit multiplication | 2(3+4) | 14 |
| Degree trig | sin(30) in DEG | 0.5 |
| Discontinuity | Y1 = 1/x | 400 points (x = 0 skipped), no fake vertical line at the origin |
| Trig asymptotes | Y1 = tan(x) | 401 points; the curve breaks at each asymptote instead of drawing spikes |
| Float display | 0.1+0.2 | 0.3 (10-digit display rounding) |
| Two functions | Y1 = x^2, Y2 = 2*x+1 | Both curves plus exact traced intersection values |
What competing TI-84 tools get wrong or miss
Most online TI-84 tools are full emulators that copy the handheld key for key. They work, but they inherit the handheld’s menu maze: 2nd and ALPHA layers, MODE screens, and STAT menus that take longer to learn than the math they are meant to help with. This page follows the browser-replica pattern instead: three clean tabs, no key-chord memorization, and the math shown in the open.
Four honest differences are worth your time. First, asymptote handling: many canvas graphers connect the dots straight through a discontinuity, so 1/x gets a fake vertical spike at x = 0. This grapher breaks the line wherever the jump between samples is too steep, so tan(x) draws as separate branches the way it should. Second, the angle toggle never hides: the current mode is printed next to every scientific result (for example sin(30) [DEG]), where several rivals leave you guessing after a page reload. Third, the info line tells you what was sampled: 401 points, y in [0, 100] is shown under every graph, so a blank-looking plot is diagnosable instead of mysterious. Fourth, the affiliation is stated plainly: this is a TI-84-style tool built for this page, not Texas Instruments software. If you want a deliberately lighter tool without the graphing tabs, the T84 calculator page on this site offers a simplified quick-calc instead of the full three-mode simulator.
One thing no competitor can fix for you: exam boards require the physical handheld. The TI-84 Plus family is approved for the SAT, ACT, PSAT/NMSQT, AP exams and IB Mathematics, but those approvals cover the battery-operated device, not a browser tab. Practicing here builds the same muscle memory; on exam day you still bring the real calculator.
What this tool is not: the Texas Instruments note
This is a TI-84-style tool built for this page. It is not made, sold, endorsed or certified by Texas Instruments, it does not run the TI-84 operating system, and “TI-84” in the title describes the style of calculator, the way “karaoke-style” describes a microphone. If you need the genuine article, including matrices, TI-BASIC programming and the exact exam-approved behavior, Texas Instruments’ own product page for the TI-84 Plus CE family describes the real device and its exam approvals.
The honest limits: there is no matrix mode, no equation solver, no TI-BASIC, and no complex-number support. The cbrt function errors on negative inputs instead of returning −3. Statistics needs at least two numbers (two pairs for regression), and tracing needs a hover or tap on the graph, which is awkward on some touch setups. Everything on the page runs locally in your browser; nothing you type is sent anywhere.
Frequently asked questions
No. This is a TI-84-style tool built for this page. It is not made, sold, endorsed or certified by Texas Instruments, and it does not run the TI-84 operating system. It reproduces the three workflows students use most: scientific evaluation, function graphing with trace and zoom, and statistics with linear regression.
No. Exam boards require an approved physical handheld calculator; online tools are not permitted in the testing room. The TI-84 Plus family itself is approved for the SAT, ACT, PSAT/NMSQT, AP exams and IB Mathematics, so practice here and bring the real device on exam day.
The calculator starts in radians, exactly like a real TI-84. In radians, sin(30) is -0.9880316241. Tap the RAD button to switch to degrees, then sin(30) gives 0.5. The angle mode is printed next to every result, for example sin(30) [DEG], so the mode is never a mystery.
The engine computes cube roots as a fractional power, and a negative base with a fractional exponent is not a real number in that arithmetic, so it reports “Result is not a real number” instead of guessing. A physical TI-84 returns -3 here. This is a known limitation of this tool, disclosed rather than hidden.
The grapher samples each function 400 times and breaks the drawn line wherever the jump between two samples is too steep. That keeps tan(x) as separate branches instead of drawing fake vertical spikes at the asymptotes. Points that cannot be evaluated, like x = 0 for 1/x, are simply skipped: the info line reports 400 points instead of 401.
By linear interpolation between the closest ranks: with the sorted data, the position is (n – 1) times the percentile, and the value is interpolated between the two surrounding data points. This is the same method Microsoft Excel uses for its percentile function, so results match Excel on the same data.
No, and the degree toggle does not affect graphing at all: the grapher always uses radians. To plot sin(x) in degrees, enter sin(x*pi/180) instead. The scientific mode is the only tab with the RAD/DEG toggle.
Yes to both. Each mode has “Copy my results” and “Share results” buttons once you calculate. To embed the whole calculator, use the “Add This Calculator to Your Website” section below: pick a size, preview it, and copy the code.
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Embed this calculator on your own site with the code below. Pick a size to preview it live, then copy the code.
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References
- Texas Instruments. TI-84 Plus CE Family Graphing Calculators (the real device: graphing, statistics and exam approvals for SAT, ACT, PSAT/NMSQT, AP and IB; this page is not affiliated with TI). Accessed October 24, 2026.
- College Board. SAT Suite of Assessments Calculator Policy (only approved handheld calculators may be used; tablets, laptops and phones are prohibited). Accessed October 24, 2026.
- ACT, Inc. ACT Test Day Checklist: What to Bring (bring a permitted calculator for the math test; electronic devices must be off and out of sight). Accessed October 24, 2026.
- College Board. AP Exams Calculator Policy (approved handheld graphing calculators only; web-based calculators are not permitted during exams). Accessed October 24, 2026.
- National Institute of Standards and Technology. Engineering Statistics Handbook: Percentiles (nine percentile methods; the linear-interpolation R7 method used by Excel and by this calculator). Accessed October 24, 2026.
- Penn State Eberly College of Science. STAT 501: What is the “Best Fitting Line?” (least-squares criterion and the slope/intercept formulas behind this tool’s regression mode). Accessed October 24, 2026.