FluentFacts
Include Zero (0) Facts

Allow 0 as an addend (e.g. 4 + 0 = 4)

Seed #42 · 20 Facts
8.5" × 11" Letter Preview·20 Facts·vertical layout

Missing-Number Math Worksheets

Solve each math problem carefully. Check your answers when finished!

Name:
Date: 
Score:/ 20
Time: 
1)
7
+?
12
2)
7
+?
9
3)
3
+?
10
4)
5
+?
8
5)
?
+4
12
6)
6
+?
13
7)
1
+?
6
8)
?
+6
7
9)
?
+1
4
10)
?
+6
14
11)
?
+9
11
12)
?
+4
13
13)
1
+?
2
14)
6
+?
9
15)
3
+?
7
16)
?
+6
15
17)
?
+3
6
18)
7
+?
14
19)
10
+?
11
20)
?
+10
15
Fluent Facts·Free Math Fact Fluency Worksheet Generator
worksheets.fluentfacts.com·Page 1 of 2

[ANSWER KEY] Missing-Number Math Worksheets

Solve each math problem carefully. Check your answers when finished!

Name:Answer Key
Date: 
Score:20/ 20
Time: 
1)
7
+5
12
2)
7
+2
9
3)
3
+7
10
4)
5
+3
8
5)
8
+4
12
6)
6
+7
13
7)
1
+5
6
8)
1
+6
7
9)
3
+1
4
10)
8
+6
14
11)
2
+9
11
12)
9
+4
13
13)
1
+1
2
14)
6
+3
9
15)
3
+4
7
16)
9
+6
15
17)
3
+3
6
18)
7
+7
14
19)
10
+1
11
20)
5
+10
15
Fluent Facts·Free Math Fact Fluency Worksheet Generator
worksheets.fluentfacts.com·Page 2 of 2
Page 2 Preview (Answer Key):Will automatically print on page 2

[ANSWER KEY] Missing-Number Math Worksheets

Solve each math problem carefully. Check your answers when finished!

Name:Answer Key
Date: 
Score:20/ 20
Time: 
1)
7
+5
12
2)
7
+2
9
3)
3
+7
10
4)
5
+3
8
5)
8
+4
12
6)
6
+7
13
7)
1
+5
6
8)
1
+6
7
9)
3
+1
4
10)
8
+6
14
11)
2
+9
11
12)
9
+4
13
13)
1
+1
2
14)
6
+3
9
15)
3
+4
7
16)
9
+6
15
17)
3
+3
6
18)
7
+7
14
19)
10
+1
11
20)
5
+10
15
Fluent Facts·Free Math Fact Fluency Worksheet Generator
worksheets.fluentfacts.com·Page 2 of 2

Made for everyday practice

Missing-Number Math Worksheets

Practice finding an unknown number rather than only calculating a total. The generator starts with missing addends in addition facts within 20. Switch operations and choose a missing-factor or missing-number option for other practice.

Free to use, with no account required. Customize the worksheet above, include an answer key, and print or save your math facts practice as a PDF.

Choose one unknown at a time

Begin with a consistent missing-number position. When learners understand the relationship, select Mixed missing positions. Ask them to substitute their answer back into the equation to check it.

Think about the relationship

For 7 + □ = 12, ask what must be added to 7 to reach 12. Learners can count on, use a known combination, or subtract 7 from 12. Compare the strategies rather than guessing.

The missing addend in 7 + □ = 12 is 5. For multiplication, 3 × □ = 18 asks which number of groups of 3 makes 18: the missing factor is 6.

How to print or save as PDF

  1. Choose your operation, difficulty, and number of problems above.
  2. Use Shuffle for fresh facts. Turn on “Print Answer Key Page” if you want a separate answer page.
  3. Select “Print Worksheet.” Choose your printer or your browser’s “Save as PDF” destination.

Designed for US Letter paper. Check the print preview and turn off browser headers and footers for a cleaner worksheet.

Keep practicing with FluentFacts

Try these same facts on screen, or explore a related operation. Connect addition with subtraction and multiplication with division to reinforce the relationships.

Practice these facts on screenExplore related facts →

Worksheet questions

Is this math facts generator free?

Yes. Create and print worksheets without signing up or paying for a subscription.

Can I include an answer key?

Yes. Enable “Print Answer Key Page” in the worksheet settings to print a separate answer page. “Preview Answers” shows solutions on screen so you can check your work before printing.

Can I download a worksheet as a PDF?

Use “Print Worksheet,” then select “Save as PDF” in your browser’s print dialog where available. The generator uses your browser’s printing tools rather than a separate PDF download.

How do I change the difficulty or get new problems?

Adjust the number ranges and operation-specific options in the settings. Use Shuffle to generate a new set of facts while keeping your chosen settings.