How do you compare two decimals?

Line up the decimal points and compare the digits from left to right. The first place where the digits differ decides which number is larger.

Why add trailing zeros when comparing?

Adding zeros to the end of a shorter decimal gives both numbers the same number of places, so you can compare them digit by digit without confusion.

Does a longer decimal mean a bigger number?

No, length does not decide size. A number with more digits after the point can still be smaller, because place value matters more than how many digits there are.

Where is comparing decimals useful?

It is used for money, measuring length or weight, comparing sports times, and reading charts, where small differences between values often matter a lot.

Comparing Decimals

Math Interactive lesson Free to play

Comparing decimals means working out which of two or more decimal numbers is larger, smaller, or exactly equal. You do it by looking at place value — the whole-number part first, then the tenths, then the hundredths, and so on, moving from left to right. The first place where the digits differ decides the answer. A handy trick is to line up the decimal points and, if one number is shorter, add zeros to the end so both have the same number of decimal places; this makes a digit-by-digit comparison easy. A common mistake is thinking a number with more digits must be bigger, but that is not true — place value matters far more than length. Comparing decimals comes up constantly in real life: money, measuring length and weight, sports times, and reading charts all depend on telling which decimal value is greater.

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What this Spark covers

Which is bigger?

⚖️ 0.7 vs 0.65 Comparing Decimals Two prices, two scores, two race times… which one is bigger? Today you'll learn a simple, never-fail way to compare any two decimals. 🤔 Quick guess: is 0.7 bigger or smaller than 0.65? Keep your answer in your head — you'll find out very soon! Tap Next to begin. →
Know your places

First, name the places A decimal point splits a number into a whole part and a part smaller than one. After the dot come tenths, then hundredths. OnesTenthsHundredths 3•25 3.25 = 3 ones, 2 tenths, 5 hundredths A tenth (0.1) is one slice of a cake cut into 10 pieces. A hundredth (0.01) is much smaller — a cake cut into 100 pieces!
Whole part first

Step 1: Compare the whole part Always look at the numbers in front of the dot first. Bigger whole part = bigger decimal. The other digits don't even matter yet! Which number is bigger? Tap it. 2.9 5.1 Even though 2.9 has a big .9, 5 ones beats 2 ones. The whole part wins first!
Same whole? Go to tenths

Step 2: If wholes tie, compare tenths When the whole parts are equal, move one step right to the tenths. Let's compare 0.7 and 0.65 — the puzzle from the start! OnesTenthsHundredths 0•70 0•65 Wholes tie (0 = 0). Now compare the tenths: Pick the correct sign for 0.7 ⬚ 0.65 > = <
The longer-number trap

Watch out: longer ≠ bigger! With whole numbers, more digits means bigger. With decimals, that's not true. 0.65 has more digits than 0.7, but 0.7 is bigger! A neat trick: add a zero so both have the same length. OnesTenthsHundredths 0•70 0•65 0.7 is really 0.70. And 70 hundredths > 65 hundredths. ✅ Now you try! Which is bigger? 0.4 0.39
The 3-step recipe

Your never-fail recipe Tap each step to reveal it. Compare 3.45 and 3.5 as you go: 1 Tap to reveal… 2 Tap to reveal… 3 Tap to reveal…
You're the judge

Final challenge Use the recipe. Pick the right sign for 1.08 ⬚ 1.5 OnesTenthsHundredths 1•08 1•50 Wholes tie (1 = 1). Look at the tenths: 0 vs 5. > = < Don't be fooled by the 8 in 1.08 — those are hundredths, and tenths matter more!
You did it!

🎉 ⚖️ ✅ You can compare any decimals! 1️⃣ Compare the whole part first — bigger wins. 2️⃣ If they tie, compare tenths, then hundredths. ⚠️ Longer is not always bigger — line up the dots and add a zero (0.7 = 0.70). And the opening puzzle? 0.7 > 0.65 — now you know exactly why. Brilliant work! 🌟

Frequently asked questions

How do you compare two decimals?: Line up the decimal points and compare the digits from left to right. The first place where the digits differ decides which number is larger.
Why add trailing zeros when comparing?: Adding zeros to the end of a shorter decimal gives both numbers the same number of places, so you can compare them digit by digit without confusion.
Does a longer decimal mean a bigger number?: No, length does not decide size. A number with more digits after the point can still be smaller, because place value matters more than how many digits there are.
Where is comparing decimals useful?: It is used for money, measuring length or weight, comparing sports times, and reading charts, where small differences between values often matter a lot.

Comparing Decimals

What this Spark covers

Frequently asked questions

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