Picture this. A question asks how much water fits in a fish tank, and the formula sheet is right there.
But which formula? And is the 10 the height or the width?
That’s where people lose points. Not on remembering formulas, but on using them. And the sheet leaves out a few you’ll still need.
Want the sheet itself? Here’s the official PDF from GED Testing Service. Below, we work out all 27 of its formulas with real numbers, each checked against that February 2026 version. Then come the 7 it leaves out.
If formulas made your head spin in school, that’s okay. You don’t need to love them. You need to recognize a handful on sight, and that comes from using each one a few times.
Every formula on the sheet, worked out with real numbers
Tap any formula to see it used on a real problem. Searching works too: try “cone” or “slope”.
These match the official Mathematics Formula Sheet (2026-02 revised). The examples and tips are ours.
Tap any formula to see a worked example and the mistake it usually causes.
Area
Area is the space inside a flat shape, always measured in square units.
Perimeter
Perimeter is the distance all the way around a shape, measured in ordinary units.
Circumference
Surface area and volume
On the sheet, p is the perimeter of the base, B is the area of the base, and s in the pyramid and cone formulas is the slant height.
Data
Algebra
The 7 formulas the sheet leaves out (learn these)
The sheet covers shapes well. Money and percents? Not so much.
These can still show up on the test, so learn them before test day:
| Not on the sheet | What to do instead |
|---|---|
| Compound interest | Only simple interest, I = Prt, appears. Compound-interest questions do appear, so learn A = P(1 + r/n)^(nt) separately. |
| Percent change | There is no percent-increase or percent-decrease formula. Use (new − old) ÷ old, then multiply by 100. |
| Distance between two points | The sheet has d = rt, which is for travel, and no coordinate-plane distance formula. On the grid, build a right triangle and use a² + b² = c². |
| Midpoint formula | Not provided, so average the x-values and average the y-values. |
| Unit conversions | No conversion table is given. Common ones have to be known: 12 inches in a foot, 3 feet in a yard, 16 ounces in a pound, 60 minutes in an hour. |
| Exponent rules | The sheet does not list them. Know that multiplying like bases adds exponents and dividing subtracts them. |
| Probability formulas | No counting or probability formula appears. Probability is favorable outcomes ÷ total outcomes. |
If you only learn one, make it percent change.
A $40 shirt is marked down to $30. What’s the percent decrease?
The working
- Find the drop: $40 − $30 = $10.
- Divide by the original price: 10 ÷ 40 = 0.25.
- Turn it into a percent: 0.25 × 100 = 25%.
Dividing by the new price ($30) instead is the most common slip.
Answer: 25%
Practice it in fractions, decimals and percents. The exponent rules are in exponents and roots.
Know where things are before test day
Think of the sheet like a grocery store you shop at every week. You don’t read every aisle sign. You just know where the milk is.
The sheet runs in this order: area, perimeter, circumference, surface area and volume, data, then algebra.
Here’s why that matters. You get about 46 questions in 115 minutes, roughly two and a half minutes each. Hunting for the cone formula eats into that.
The fix: open the sheet every time you practice, even when you think you remember the formula. Our full practice test keeps it one click away on every question, so the habit builds itself.
Mistake 1: the right formula, the wrong letter
Most formula mistakes don’t happen when you pick the formula. They happen when you plug in the numbers. The three classic slips:
- Using the diameter (all the way across a circle) where the formula wants the radius (half of it).
- Using the slanted side of a cone or a parallelogram instead of its straight-up height. The parallelogram lesson shows how to spot it.
- Reading the b in y = mx + b as “base”. It’s the starting value, like a $45 monthly fee before any extras.
The fix takes five seconds. Before you calculate, write down what each letter equals: r = 3, h = 10. Then plug in.
Watch the diameter most of all. Squaring the full diameter gives an answer four times too big, and that wrong answer is often one of the choices.
Mistake 2: the right number, the wrong units
Picture a bedroom. The baseboard around the edge is measured in feet. The carpet on the floor is in square feet. The air inside is in cubic feet.
Same room, three different units. Perimeter and circumference are plain units, area is square units, and volume is cubic units.
When two answer choices show the same number with different units, the question is checking whether you know what you just measured. Read the unit before you click.
Mistake 3: forgetting the sheet when the calculator is off
The test starts with about five questions where you can’t use a calculator. The formula sheet is still there for those, and people forget that.
Those questions use friendly numbers you can work out by hand, but you may still need a formula to set one up. Our GED calculator guide explains how the two parts work.
Bottom line: the sheet is there for every question. Use it whenever a shape, a line or money shows up.
How to make the formulas stick in about a week
Reading the sheet won’t do it. Using each formula a few times, getting some wrong and seeing why, will. Here’s a simple plan:
- Days 1 and 2: geometry and measurement. Volume and surface area have the most letters, so they cause the most slips.
- Days 3 and 4: functions and graphing, for slope and the line formulas.
- Day 5: data and statistics, for mean and median.
- Days 6 and 7: percents, for percent change and interest, the formulas the sheet leaves out.
Frequently asked questions
Do you get a formula sheet on the GED math test?
Yes. It's on paper at a test center and in a drop-down menu if you test online. You can use it on every question, including the first few where there's no calculator.
Do I have to memorize formulas for the GED math test?
Not the ones on the sheet. You do need a few it leaves out, like percent change, compound interest and common unit conversions. The table on this page lists all seven.
What formulas are on the GED math formula sheet?
Area, perimeter, circumference, surface area and volume for the common shapes, mean and median, and the main algebra formulas: slope, slope-intercept and point-slope form, the quadratic formula, the Pythagorean theorem, simple interest, distance and total cost.
Is the quadratic formula on the GED formula sheet?
Yes, along with the standard form y = ax² + bx + c. Some sites say it isn't, but it's on the February 2026 sheet. You don't need to memorize it. You do need to know how to plug in a, b and c.
Are compound interest and percent change on the sheet?
No. The sheet only has simple interest, I = Prt, and it has no percent change formula. Learn A = P(1 + r/n)^(nt) and (new − old) ÷ old × 100 before test day.
Can I bring my own formula sheet or cheat sheet to the GED test?
No. Notes of any kind aren't allowed, so the official sheet is the only cheat sheet you get. Practice with it until you know where things are.
Where can I get the official GED formula sheet PDF?
GED Testing Service posts it on ged.com. The current file is the February 2026 revision, and there's a link to it just above the formula list on this page.
Written by
Coach Crissy
Math instructor
Coach Crissy teaches the video lessons behind the BooknBoost GED math course, working through GED-style problems on camera: ratios and proportions, percent and interest, mean, median and mode, slope, and the geometry students meet on test day.
Keep going
Free full-length practice test
46 questions with the formula sheet on every screen, and every answer explained.
The TI-30XS calculator on the GED
Which keys matter, when it's locked, and whether you can bring your own.
Geometry and measurement practice
The formulas with the most letters, and the ones that cause the most slips.
The full study guide
Each skill on the test mapped to practice, with a week-by-week plan.