Difference Between CHAR and VARCHAR in SQL

Feature	CHAR(n)	VARCHAR(n)
Meaning	Fixed-length string	Variable-length string
Storage	Always exactly n characters	Only stores the actual length used (up to n)
Padding	Pads with spaces if shorter than n	No padding — stores only the actual characters
Performance	Slightly faster for fixed-size values	More storage-efficient for variable sizes
Use Case	When all values are about the same length	When values vary widely in length
Example	CHAR(5) always stores 5 characters	VARCHAR(5) stores 1–5 characters

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1. CHAR(n) — Fixed Length

• Always exactly n characters.
• If the input is shorter, it’s padded with spaces.
• Faster for fixed-length data because the database knows exactly how much space each value takes.

✅ Example:

CREATE TABLE ExampleChar (
    code CHAR(5)
);

Insert:

INSERT INTO ExampleChar (code) VALUES ('A1');

code
A1

Always takes 5 bytes (assuming 1 byte per character, like in ASCII).

2. VARCHAR(n) — Variable Length

• Stores only the characters you provide (up to n).
• No extra spaces.
• More storage efficient when lengths vary a lot.

✅ Example:

CREATE TABLE ExampleVarchar (
    code VARCHAR(5)
);

Insert:

INSERT INTO ExampleVarchar (code) VALUES ('A1');

code
A1

Takes only 2 bytes for A1, plus 1–2 bytes extra to store the length internally (depends on DB engine).

When Should You Use CHAR vs VARCHAR?

Use CHAR When	Use VARCHAR When
Data is always fixed length	Data is variable length
Example: country codes (US, FR)	Example: names, emails, descriptions
Speed is a tiny bit more important	Storage efficiency is important
Minor gain for huge tables	Better if length varies a lot

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Real-World Example

Field	Type	Why
Country code	CHAR(2)	Always 2 characters — US, FR, JP.
User email	VARCHAR(255)	Varies a lot — from short to very long addresses.
Phone number	CHAR(10)	Always 10 digits (in some countries).
Address	VARCHAR(500)	Highly variable.

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In Short

CHAR(n): Fixed-length string — always n characters, padded with spaces.
VARCHAR(n): Variable-length string — stores exactly what you insert, no padding.