unity-save-load

name	unity-save-load
description	Unity Save/Load and Data Persistence

Unity Save/Load and Data Persistence

Use this skill when implementing save/load systems, persisting game state to disk, managing PlayerPrefs, or building serialization pipelines for game data.

PlayerPrefs — Simple Key-Value Storage

PlayerPrefs stores small amounts of data in OS-specific locations (registry on Windows, plist on macOS). Use for settings only, not game saves.

// Writing
PlayerPrefs.SetInt("HighScore", 9999);
PlayerPrefs.SetFloat("MasterVolume", 0.8f);
PlayerPrefs.SetString("PlayerName", "Totes");
PlayerPrefs.Save(); // flush to disk (automatic on Application.Quit)

// Reading (with defaults)
int highScore = PlayerPrefs.GetInt("HighScore", 0);
float volume = PlayerPrefs.GetFloat("MasterVolume", 1.0f);
string name = PlayerPrefs.GetString("PlayerName", "Player");

// Checking existence
if (PlayerPrefs.HasKey("MasterVolume")) { /* ... */ }

// Deleting
PlayerPrefs.DeleteKey("MasterVolume");
PlayerPrefs.DeleteAll(); // nuclear option — settings reset

Limitations:

• Not secure (plain text in registry/plist)
• No structured data (no arrays, no objects)
• Platform-specific storage locations
• Do NOT use for save games — use JSON/binary files instead

Resources Folder

Resources.Load is synchronous and convenient but has downsides:

// Load from Assets/Resources/
var prefab = Resources.Load<GameObject>("Prefabs/Enemy");
var texture = Resources.Load<Texture2D>("Textures/icon");
var all = Resources.LoadAll<AudioClip>("Audio/SFX");

Why to avoid Resources:

• ALL assets in Resources/ are included in the build, even if unused
• Cannot be unloaded individually
• Causes longer build times
• No async loading
• Prefer Addressables for anything beyond prototyping

StreamingAssets

Files in Assets/StreamingAssets/ are included in the build as-is (not processed by Unity). Useful for raw config files, databases, or pre-built data.

// Read a file from StreamingAssets
string path = Path.Combine(Application.streamingAssetsPath, "config.json");

// Platform differences:
// Windows/Mac/Linux: file:// path, can use File.ReadAllText
// Android: jar:// path, must use UnityWebRequest
// WebGL: http:// path, must use UnityWebRequest

#if UNITY_ANDROID && !UNITY_EDITOR
    // Android requires UnityWebRequest
    using var www = UnityWebRequest.Get(path);
    yield return www.SendWebRequest();
    string json = www.downloadHandler.text;
#else
    string json = File.ReadAllText(path);
#endif

Summary — When to Use What

Method	Use Case	Pros	Cons
PlayerPrefs	Settings (volume, quality)	Simple, cross-platform	Not secure, no structured data
JsonUtility	Simple save data, no Dictionary	Fast, zero dependencies	Limited type support
Newtonsoft.Json	Complex save data, Dictionary, polymorphism	Full-featured	External dependency
Custom binary	Performance-critical or large saves	Small files, fast	Manual maintenance
Addressables	Asset loading (prefabs, textures, audio)	Async, memory-managed, CDN support	Setup complexity
Resources	Quick prototyping only	Simple API	Build bloat, no async
StreamingAssets	Raw files (configs, databases)	Unprocessed, platform-native	Platform-specific loading
ScriptableObject	Game data templates (items, enemies)	Editor-friendly, reusable	Not for mutable runtime state

Topic Pages

• JSON Serialization
• Cloud Saves