You know how some programmers just open their laptops and start coding like it’s nothing? What if I told you they’re not doing what you think they’re doing? Often, they’re actually drafting pseudocode to plan out their approach.
That’s what they do….
First, they figure out the logic, plan the steps, and then they translate it into code.
And the way they do that first step? It’s called pseudocode.
Here, I’ll discover what pseudocode actually is, how to write good pseudocode, and the top examples of pseudocode use in programming scenarios.
Table of Contents
What Is Pseudocode in Programming
Pseudocode is a simple way to write down the steps of an algorithm that anyone can understand with basic programming knowledge.
It acts like a blueprint to help translate ideas into actual programming language. It includes basic programming ideas like sequence, loops, and decisions.
The best part about pseudocode? Anyone on the team can check the plan and find mistakes early. This saves time and money.
How to Write a Good Pseudocode
Everyone has their own style of writing pseudocode, because it’s meant just for humans, not computers. However, some simple guidelines can help write pseudocode more easily for everyone to understand.
- Start each line with a capital letter. This helps you see from where each step starts
- Use clear action words like GET, DISPLAY, CALCULATE, SET, ENTER, etc
- Write your plan from top to bottom, don’t skip any part.
- Use OUTPUT or DISPLAY when showing results
- Always close with END IF, END WHILE, or END FOR when you finish a section.
- Keep sentences short and simple, and avoid fancy or confusing words.
- Make your IF statements clear. Always show what happens when something is true AND what happens when it’s false
Words That Make Your Pseudocode Better
Writing pseudocode using common and clear words makes it easier to read and understand. Below is a list of some common words you can use in your pseudocode.
- GET( to receive data)
- SET (to save information)
- DISPLAY or PRINT ( to show something on screen )
- INPUT (to ask the user for information)
- OUTPUT (to give information back)
- CALCULATE (to do math)
- ADD (to combine)
- REMOVE (to take away)
- ELSE, and ELSE IF (help explain choices in the program)
- END, END IF, END WHILE, END FOR, and STOP (where sections or loops finish)
Top Examples of Pseudocodes
Example 1: Login System for Websites
Every website needs a way for users to log in. Here’s how developers plan this feature:
BEGIN UserAuthentication
INPUT username, password
IF username is empty OR password is empty THEN
DISPLAY "Please enter both username and password"
RETURN false
END IF
retrievedUser = FETCH user FROM database WHERE username matches
IF retrievedUser does not exist THEN
DISPLAY "Invalid credentials"
LOG failed_login_attempt
RETURN false
END IF
hashedPassword = HASH password with salt
IF hashedPassword matches retrievedUser.password THEN
CREATE session_token
STORE session_token in session_storage
DISPLAY "Login successful"
REDIRECT to dashboard
RETURN true
ELSE
DISPLAY "Invalid credentials"
INCREMENT failed_attempts_counter
IF failed_attempts > 3 THEN
LOCK account for 15 minutes
END IF
RETURN false
END IF
END UserAuthenticationThis plan shows how to check usernames and passwords safely. It also stops hackers who try to guess passwords many times.
Example 2: Shopping Cart for Online Stores
Online stores need to add up prices correctly. This includes discounts, taxes, and shipping costs:
BEGIN CalculateCartTotal
INITIALIZE subtotal = 0
INITIALIZE tax = 0
INITIALIZE shipping = 0
INITIALIZE discount = 0
FOR EACH item IN shopping_cart DO
subtotal = subtotal + (item.price × item.quantity)
IF item.on_sale THEN
discount = discount + (item.price × item.discount_percentage × item.quantity)
END IF
END FOR
IF customer.has_coupon THEN
coupon_discount = APPLY_COUPON(subtotal, customer.coupon_code)
discount = discount + coupon_discount
END IF
subtotal_after_discount = subtotal - discount
IF subtotal_after_discount >= FREE_SHIPPING_THRESHOLD THEN
shipping = 0
ELSE
shipping = CALCULATE_SHIPPING(customer.address, cart_weight)
END IF
tax = (subtotal_after_discount + shipping) × TAX_RATE
final_total = subtotal_after_discount + shipping + tax
RETURN {
subtotal: subtotal,
discount: discount,
shipping: shipping,
tax: tax,
total: final_total
}
END CalculateCartTotalThis pseudocode shows all the math steps before building the real program. Business teams can check if everything follows store rules.
Example 3: Sorting Numbers (Bubble Sort)
Computers often need to arrange numbers from smallest to largest. Here’s a simple way to plan this:
BEGIN BubbleSort(array)
n = LENGTH of array
FOR i FROM 0 TO n-1 DO
swapped = false
FOR j FROM 0 TO n-i-2 DO
IF array[j] > array[j+1] THEN
SWAP array[j] and array[j+1]
swapped = true
END IF
END FOR
IF swapped is false THEN
BREAK
END IF
END FOR
RETURN array
END BubbleSortBubble sort compares two numbers at once and swaps them if needed. This method helps beginners understand how sorting works.
Example 4: Finding Information Fast (Binary Search)
When looking through lots of data, binary search makes things quick:
BEGIN BinarySearch(sorted_array, target_value)
left = 0
right = LENGTH of sorted_array - 1
WHILE left <= right DO
middle = (left + right) / 2
IF sorted_array[middle] equals target_value THEN
RETURN middle
ELSE IF sorted_array[middle] < target_value THEN
left = middle + 1
ELSE
right = middle - 1
END IF
END WHILE
RETURN -1
END BinarySearchThis search method cuts the work in half each time. Instead of checking every item, it jumps to the middle and decides which half to search next.
Example 5: Checking Form Information
Programs need to check if users type the correct information into forms:
BEGIN ValidateRegistrationForm(form_data)
errors = EMPTY list
// Validate email
IF form_data.email is empty THEN
ADD "Email is required" TO errors
ELSE IF email does not match email_pattern THEN
ADD "Invalid email format" TO errors
ELSE IF EMAIL_EXISTS_IN_DATABASE(form_data.email) THEN
ADD "Email already registered" TO errors
END IF
// Validate password
IF form_data.password is empty THEN
ADD "Password is required" TO errors
ELSE IF LENGTH of form_data.password < 8 THEN
ADD "Password must be at least 8 characters" TO errors
ELSE IF password lacks uppercase, lowercase, number, or special character THEN
ADD "Password must include uppercase, lowercase, number, and special character" TO errors
END IF
// Validate password confirmation
IF form_data.password_confirm does not equal form_data.password THEN
ADD "Passwords do not match" TO errors
END IF
// Validate age
IF form_data.age < 13 THEN
ADD "Must be at least 13 years old" TO errors
END IF
IF error is empty THEN
RETURN {valid: true, errors: null}
ELSE
RETURN {valid: false, errors: errors}
END IF
END ValidateRegistrationFormForm validation catches mistakes before saving data. This keeps databases clean and users happy.
Example 6: Handling File Uploads
When users upload pictures or documents, programs must check everything carefully:
BEGIN ProcessFileUpload(uploaded_file)
MAX_FILE_SIZE = 5MB
ALLOWED_TYPES = ['image/jpeg', 'image/png', 'application/pdf']
IF uploaded_file is null THEN
RETURN error("No file selected")
END IF
IF uploaded_file.size > MAX_FILE_SIZE THEN
RETURN error("File size exceeds 5MB limit")
END IF
IF uploaded_file.type NOT IN ALLOWED_TYPES THEN
RETURN error("Invalid file type. Only JPEG, PNG, and PDF allowed")
END IF
unique_filename = GENERATE_UUID() + GET_FILE_EXTENSION(uploaded_file)
storage_path = "uploads/" + unique_filename
TRY
SAVE uploaded_file TO storage_path
IF file_type is image THEN
CREATE_THUMBNAIL(storage_path)
END IF
file_record = {
original_name: uploaded_file.name,
stored_name: unique_filename,
file_size: uploaded_file.size,
upload_date: CURRENT_TIMESTAMP,
user_id: CURRENT_USER.id
}
SAVE file_record TO database
RETURN success(storage_path, file_record.id)
CATCH error
DELETE file FROM storage_path if exists
LOG error details
RETURN error("File upload failed. Please try again")
END TRY
END ProcessFileUploadThis plan checks file size and type before saving anything. It also creates backups and handles errors smoothly.
Moving from Plans to Real Code
Once you have done writing pseudocode, the next step is to make the real program, obviously….
And it’s much easier to make a program if you already have the blueprint to follow. As a team lead, you can show pseudocode to the beginners who don’t know much about coding.
When features don’t work right, pseudocode can help you find the problem. It makes it easier for new team members to join projects. It keeps a record of how systems work for the future. Pseudocode helps people and computers understand each other.
If you learn these patterns, it will be easier and faster to solve programming problems.
Remember This!
Every person has a different style of writing pseudocode; there are no specific rules for writing it. The important thing is to write pseudocode in a way that is easy to understand for you and others as well.
Think of pseudocode like drawing a map. Everyone draws maps a bit differently, but as long as someone can follow your map and get where they need to go, your map is good!
FAQs
Pseudocode is plain language that reflects the logic of your program. It involves a common language melded with coding-like structure to demonstrate what the code will accomplish before writing it.
Programmers use pseudocode to structure their thinking process, as a mnemonic or as a way of making progress when creating an algorithm. It enables teams to agree on how a feature should work before anyone writes real code.
Not exactly. An algorithm is a general method or scheme for solving a problem. Pseudo code is the way you write that algorithm down, in a form that’s human-readable and step-by-step.
No. There is no prescribed syntax for pseudocode. The goal is clarity. There cannot be any one right answer, as long as your logic is good and people can understand your steps, then your Pseudocode is fine.
Typical keywords are INPUT, OUTPUT, IF, ELSE, WHILE, FOR, SET, CALCULATE, and END. And these are words that the logic parses nicely and well.
Both. In the professional world, pseudocode is used to scope out features, describe logic to non-technical people and provide documentation on how systems function.
It’s a way to learn logic by learning without fear of syntax errors.” Beginners can start by comprehending how a program runs, even without coding.
Program flow is visualized in flowcharts using graphs (flow diagrams). Pseudo code uses natural language to describe the same idea. Both have the simple goal, but in other forms.
While some tools and AI assistants can translate pseudocode into real programming code, they still depend on how well-written the pseudocode is.
It has just the right amount of information that, given this pseudo code, another programmer wouldn’t have to guess where exactly pairs and triples are added. But don’t overcomplicate, be clear and focused.
