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Expression notation converter

Infix to Postfix Converter

Convert mathematical infix expressions into postfix notation online. Enter an expression, get the postfix result, view stack steps, generate prefix notation, and copy or download the output.

Infix Input Stack Steps Postfix Output

Learn conversion step by step

Useful for data structures, compiler design, expression parsing, stack practice, exams, and programming assignments.

Free Infix to Postfix Converter Tool

Type an infix expression like A+B*C and convert it into postfix notation like ABC*+.

Enter Infix Expression

Supports variables, numbers, parentheses, and operators: + - * / ^
Use spaces for multi-character tokens.
Convert while typing.

Result

Postfix Expression
A B + C * D E / -
Prefix Expression
- * + A B C / D E
Expression Status
Valid expression
0 Tokens
0 Operators
0 Operands
0 Parentheses

Conversion Steps

# Token Action Stack Output
Enter an expression to see stack steps.

Quick Examples

Tip: Use spaces for multi-character variables if needed, such as total + tax * rate. The converter supports numbers, variables, parentheses, and + - * / ^ operators.

Why Use an Infix to Postfix Converter?

Infix notation is easy for humans, but postfix notation is easier for computers to evaluate using a stack.

Fast Notation Conversion

Convert infix expressions into postfix notation instantly with proper operator precedence.

Stack Step Table

View token-by-token stack actions to understand how the conversion algorithm works.

Student Friendly

Helpful for data structures, compiler design, algorithms, programming, and exam preparation.

What Is Infix to Postfix Conversion?

Infix notation places operators between operands, such as A + B. Postfix notation places operators after operands, such as A B +. Postfix is also called Reverse Polish Notation.

This converter uses a stack-based method to handle operator precedence and parentheses. Operators with higher precedence are placed earlier in the postfix output while parentheses control the order of evaluation.

How It Works

Convert infix to postfix in three simple steps.

Enter Expression

Type an infix expression using operands, operators, and parentheses.

Process Stack

The tool reads tokens from left to right and uses a stack for operators.

Get Postfix

The final postfix expression appears with stack steps, prefix output, and copy/download options.

Infix to Postfix Converter FAQs

Common questions about infix, postfix, and expression conversion.

Infix notation is the normal way of writing expressions where operators appear between operands, such as A + B.
Postfix notation places operators after operands, such as A B +. It is easy to evaluate using a stack.
This tool supports +, -, *, /, and ^ operators, along with parentheses and multi-character operands.
Yes. It shows each token, action, stack state, and output state during conversion.
No. This tool works with PHP, HTML, CSS, and JavaScript only. No database, API, or server package is needed.