Google I/O 2021 Punch Card Puzzle

7 min readMay 14, 2021

This year’s Google I/O 2021 is going to be held virtually. To reveal the event’s date Google has come up with an intriguing Punch Card Puzzle 🧩 for the developers. I would suggest you try it on your own first and if you stuck somewhere you can refer to this article.

Puzzle 1: Find the Quote

You have to find the person who said the following quote.

You can copy and paste the quote on Google to find the person.

“It matters little who first arrives at an idea, rather what is significant is how far that idea can go.”
- Sophie Germain.

As you enter “Sophie Germain” you can see the white punched rectangular bars below it representing encoding of that letter.

Puzzle 2: Spell “Hello World” on Punchcard

Here some instructions are given.

1620917736 Surely, you’ve done this before.1620917736 This year, you’ll greet the planet anew from right where you are.1620917736 Write a well-known test program composed of two words.1620917736 Often the first program written when learning to code.

From the instructions, you can make out that the well-known test program is none other than our “Hello World” program. Now you have to punch this in the card. You can take the help of the below image.

Punch Card Encoding — Punchcard Encoding

If you want to know more about punch cards you can refer to this.
We will be referring to the above image to type HELLO WORLD. In the puzzle 11th and 12th rows are empty.
Let’s refer to these empty rows 12 & 11 as X & Y.
Example: H will now be equal to X 8

Follow the below pattern and punch:

H - X 8
E - X 5
L - Y 3
L - Y 3
O - Y 6
Space
W - 0 6
O - Y 6
R - Y 9
L - Y 3
D - X 4

After your submission, you will see a cool animation of a rotating Globe 🌎.

Puzzle 3: Find the Quote

You have to find the person who said the following quote.

Same as puzzle 1, you can copy and paste the quote on Google to find the person.

Mathematical science is the language of the unseen relations between things. But to use and apply that language we must be able fully to appreciate, to feel, to seize, the unseen, the unconscious.
- Ada Lovelace

Puzzle 4: Complete the Punch Card

We will take the help of the above punchcard encoding image.
You are given some instructions and a bar with letters and symbols.

1620917736 The path from A to B is worn with ups and downs.1620917736 To maintain integrity, avoid adjacent punches.1620917736 No character can be used twice.1620917736 Find the diagonal way from start to finish.

We have to go from A to B but we can only go diagonally. You can see some locked columns as punch card encodings were already done for them. But there is one column just left of theB that is empty.
So, let’s fill that out. From our reference strip, we see that 2, 3, 4, 5, A, B, D is struck through so we cannot encode them again.
We have to punch on 3 to move diagonally to B but it is already struck through so we have to punch somewhere else in that column to make a different encoding.

Let’s punch:
X 3
Here X is the first empty row.

Puzzle 5: Complete the Punch Card

It is the same as the above puzzle.
We will again take the help of the above punchcard encoding image.
You are given some instructions and a bar with letters and symbols.

1620919997 The path from A to B is worn with ups and downs.1620919997 To maintain integrity, avoid adjacent punches.1620919997 No character can be used twice.1620919997 Find the diagonal way from start to finish.

We again have to go from A to B but we can only go diagonally. You can see some locked columns as punch card encodings were already done for them.
So, let’s fill out the remaining columns. From our reference strip, we see that A, N, O, L, U, C, K, Bare struck through so we cannot encode them again.

Let’s assume the first two empty rows as X and YWe have to print:A S 3 4 N O 7 6 5 D L U C K / Z M E P Y J 2 1 0 Q & - B
Follow the below pattern and punch (Leave the locked ones):

A - Locked
S - 0 2
3
4
N - Locked
O - Locked
7
6
5
D - X 4
L - Locked
U - Locked
C - Locked
K - Locked
“/” - 0 1
Z - 0 9
M - Y 4
E - X 5
P - Y 7
Y - 0 8
J - Y 1
2
1
0
Q - Y 8
“&” - X
“-” - Y
B - Locked

Puzzle 6: Complete the Punch Card

It is the same as the above puzzle.
We will again take the help of the above punchcard encoding image.
You are given some instructions and a bar with letters and symbols.

1620929612 The path from A to B is worn with ups and downs.1620929612 To maintain integrity, avoid adjacent punches.1620929612 No character can be used twice.1620929612 Find the diagonal way from start to finish.

We have to go from C to Dbut we can only go diagonally. You can see some locked columns as punch card encodings were already done for them.
So, let’s fill out the remaining columns. From our reference strip, we see that C, O, N, T, A, S, K, Dare struck through so we cannot encode them again.

Let’s assume the first two empty rows as X and YWe have to print: C45ON*321TASKBM0L&-/J:#@’=VWXYPFGHIQR”7;?(98Z+|6)D
Follow the below pattern and punch (Leave the locked ones):

C - Locked
4
5
O - Locked
N - Locked
“*” - Y 4 8
3
2
1
T - Locked
A - Locked
S - Locked
K - Locked
B - X 2
M - Y 4
0
L - Y 3
& - X
“-” - Y
“/” - 0 1
J - Y 1
“:” - 2 8
“#” - 3 8
“@” - 4 8
‘ - 5 8
“=” - 6 8
V - 0 5
W - 0 6
X - 0 7
Y - 0 8
P - Y 7
F - X 6
G - X 7
H - X 8
I - X 9
Q - Y 8
R - Y 9
“ - 7 8
7
“;” - Y 6 8
“?” - 0 7 8
“(” - X 5 8
9
8
Z - 0 9
“+”- X 6 8
“|”- X 7 8
6
“)”- Y 5 8
D - Locked

After submitting you will see a cool animation 👾

Puzzle 7: Find the quote

You have to find the person who said the following quote.

Same as the above puzzles, you can copy and paste the quote on Google to find the person.

“Information by itself never does anything. It still consists of a human being who turns it into something we might call knowledge.”
- Grace Hopper

Puzzle 8: Sort the Punch Cards

Instruction is given.

1620934596 Sort in a timely fashion.

We have to sort the punch cards from back to front.
The order is: Blue💙 Red❤️ Orange🧡 Green💚

After submitting you will see a cool animation 🧬

Puzzle 9: Find the quote

You have to find the person who said the following quote.

Same as the above puzzles, you can copy and paste the quote on Google to find the person.

“I was able to stand on the shoulders of those women who came before me, and women who came after me were able to stand on mine.”
- Christine Darden

Puzzle 10: Sort all the punch cards

You will see many punch cards lined up in front of you. Instruction is also given.

1620936124 Though there are many, now is the time everything comes together.

First, click on the sort() button at the bottom right. Order statements correctly from 1 to 6

Then navigate to the 79 column by holding down the right arrow key(->) .
Click on sort(79) to sort the column.
Similarly, navigate to 78, 77, 76, 75, 74, 73, 72, 71, 70 and perform the sort(c) in this order.

After submitting, Google will reveal its I/O 2021 Event Date. And, later it will redirect you to the events page to register.

You can register on the event’s page to earn the Attendee I/O ’21 badge for your Google Developer profile.
Here is mine (You have to be signed in to view my profile).