How to Create a Save System in Unity Using JSON

Why You Need a Save System in Unity

If your game has:

• Player progress
• Levels
• Inventory
• Health or stats
• Unlockable content

You need a save system.

Without saving, players lose progress every time they close the game. That is frustrating and game-breaking.

The good news is: building a save system in Unity using JSON is simple and beginner-friendly.

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Why Use JSON for Saving Data?

JSON is:

• Human-readable
• Lightweight
• Easy to debug
• Built into Unity with JsonUtility

It is perfect for storing structured data like player stats and game progress.

Example of JSON data:

{
  "playerName": "Hero01",
  "level": 5,
  "health": 80,
  "coins": 150
}

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Step 1: Create a Data Class

First, create a C# class that represents the data you want to save.

[System.Serializable]
public class PlayerData
{
    public string playerName;
    public int level;
    public int health;
    public int coins;
}

Important: The class must be marked as [System.Serializable] for Unity’s JsonUtility to work.

This class defines what will be saved.

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Step 2: Create a Save Manager Script

Now create a script called SaveManager.cs.

using UnityEngine;
using System.IO;

public class SaveManager : MonoBehaviour
{
    private string filePath;

    private void Awake()
    {
        filePath = Application.persistentDataPath + "/playerdata.json";
    }

    public void SaveGame(PlayerData data)
    {
        string json = JsonUtility.ToJson(data, true);
        File.WriteAllText(filePath, json);
        Debug.Log("Game Saved to: " + filePath);
    }

    public PlayerData LoadGame()
    {
        if (File.Exists(filePath))
        {
            string json = File.ReadAllText(filePath);
            PlayerData data = JsonUtility.FromJson<PlayerData>(json);
            Debug.Log("Game Loaded");
            return data;
        }
        else
        {
            Debug.Log("No Save File Found");
            return null;
        }
    }
}

This script:

• Converts data to JSON
• Writes it to a file
• Reads it back when needed

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Step 3: Connect It to Your Player

Now let’s use it inside your Player script.

public class Player : MonoBehaviour
{
    public string playerName;
    public int level;
    public int health;
    public int coins;

    public SaveManager saveManager;

    public void Save()
    {
        PlayerData data = new PlayerData();
        data.playerName = playerName;
        data.level = level;
        data.health = health;
        data.coins = coins;

        saveManager.SaveGame(data);
    }

    public void Load()
    {
        PlayerData data = saveManager.LoadGame();

        if (data != null)
        {
            playerName = data.playerName;
            level = data.level;
            health = data.health;
            coins = data.coins;
        }
    }
}

Now your player can:

• Save progress

• Load previous data

You can connect these methods to UI buttons.

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Where Does Unity Save the File?

Unity uses:

Application.persistentDataPath

This ensures:

• Windows saves correctly

• Android saves correctly

• iOS saves correctly

• Console builds work properly

Never hardcode file paths.

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Improving the Save System

Once the basic system works, you can improve it.

Add Encryption

To prevent cheating, you can:

• Encode the JSON

• Encrypt the file

• Use Base64 encoding

Add Auto Save

Call Save():

• After level completion

• After checkpoints

• On application quit

Save Multiple Files

You can create:

• Player profile saves

• Settings saves

• Inventory saves

• World state saves

Just change file names.

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Common Beginner Mistakes

Forgetting [Serializable]

Without it, Unity cannot convert your class to JSON.

Not Checking File Exists

Always verify before loading.

Overwriting Data Accidentally

Be careful when auto-saving.

Saving Too Frequently

Writing to disk constantly can affect performance.

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When to Use JSON vs PlayerPrefs

Use JSON when:

• You have structured data

• You need complex objects

• You want readable save files

Use PlayerPrefs when:

• Saving small values

• Storing simple settings

• Managing volume, resolution, toggles

JSON is better for real game progress.

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Scaling This System

As your game grows, you may want:

• ScriptableObject integration

• Cloud saves

• Versioned save files

• Save slot management

• Binary serialization for performance

But JSON is the perfect starting point.

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Apptastic Insight

A save system is not just a technical feature.

It protects the player’s time.

Even beginner games feel professional when:

• Progress is preserved

• Data loads correctly

• Players trust the system

Start simple.

Build clean.

And let your players continue their journey exactly where they left off.