How to Square Numbers in Your Head Using Simple Patterns

Squaring numbers in your head might sound like a party trick — but it’s actually one of the most useful (and fun) mental math skills you can develop.
From speeding up your calculations in exams to surprising your friends with lightning-fast math, knowing how to square numbers using patterns and shortcuts can save time and boost confidence.
And the best part? It’s easier than you think.
Why Learn to Square Mentally?
Whether you’re prepping for competitive exams, working with finance, or just love number games, squaring is everywhere. For example:
- Area calculations
- Algebra and formulas
- Interest rate math
- Estimating large values quickly
So instead of reaching for a calculator every time, let’s train your brain to do the heavy lifting — fast.
The Core Idea: Look for Patterns
Numbers are full of patterns — and squaring reveals some of the coolest.
We’ll go through a few techniques, step-by-step, and by the end of this post, you’ll be squaring like a pro.
1. Numbers Ending in 5
This is one of the most famous Vedic Math tricks.
Example: 35²
Step 1: Take the first digit (3)
Step 2: Multiply it by the next number (3 × 4 = 12)
Step 3: Add 25 at the end
Answer: 1225
Works for all numbers ending in 5:
- 25² = 625
- 65² = 4225
- 95² = 9025
2. Use the Identity: (a + b)² = a² + 2ab + b²
This formula is super handy if the number is near a round number.
Example: 42²
Split as 40 + 2
→ 40² = 1600
→ 2 × 40 × 2 = 160
→ 2² = 4
Add them: 1600 + 160 + 4 = 1764
Works great for numbers like 62, 48, 71, etc.
3. Base Method (Great for Numbers Near 100)
If the number is close to 100, use this pattern: (100 + x)² = 10000 + 200x + x²
Example: 103²
→ 100 + 3 = 103
→ 10000 + 200 × 3 + 9 = 10000 + 600 + 9 = 10609
It also works for numbers less than 100:
Example: 97²
→ 100 - 3 = 97
→ 10000 - 600 + 9 = 9409
4. Use the Difference of Squares
When squaring numbers like 89, use: a² = (a + b)(a - b) + b²
Example: 89²
Think:
89 = 90 - 1
→ 90 × 88 = 7920
→ Add 1² = 7920 + 1 = 7921
You’re using easy multiplication instead of squaring directly.
5. Squaring Numbers Between 30–70 (Break & Balance)
If it’s tricky, break the number in half and square each side.
Example: 46²
→ Think 46 = 50 - 4
→ 50² = 2500
→ 4² = 16
→ Subtract 2 × 50 × 4 = 400
So: 2500 - 400 + 16 = 2116
Once you get the hang of it, these steps take less than 10 seconds in your head.
Pro Tips for Practice
- Start small: Try 2-digit numbers under 50 first
- Time yourself: See how fast you get
- Mix it up: Try a different method each day
- Quiz a friend or challenge yourself while commuting
Mental squaring improves focus, number memory, and pattern recognition — making you sharper in all areas of math.
Final Thought: Turn Math Into Magic
Mental squaring isn’t just about speed — it’s about seeing math as a language of patterns.
The more you practice, the more you’ll notice the shortcuts hiding in plain sight.
And soon, you won’t just be solving problems — you’ll be solving them beautifully.
So the next time someone says, “What’s 85 squared?”, smile and say: “It’s 7225.”
No calculator needed.