Inspector and serialization attributes

Unity 6 reference

At a glance

These attributes control what Unity saves and how fields appear in the Inspector. The two questions are separate: a field can be serialized but hidden, or visible only because it is serializable.

Quick reference

Attribute	What it does	Applies to and requires
[SerializeField]	Make a private field part of Unity serialization and show it in the Inspector.	Field · UnityEngine
[HideInInspector]	Hide a serialized field from the Inspector without necessarily removing its saved data.	Field · UnityEngine
[NonSerialized]	Stop a public field from being serialized using the .NET attribute.	Field · System
[FormerlySerializedAs("oldName")]	Preserve serialized field values after a field is renamed.	Field · UnityEngine.Serialization
[Header("Title")]	Add a heading above a field in the Inspector.	Field · UnityEngine
[Space] / [Space(n)]	Add vertical space before a field in the Inspector.	Field · UnityEngine
[Tooltip("…")]	Show explanatory text when hovering a field label.	Field · UnityEngine
[Range(min, max)]	Show a slider for an int or float field in the Inspector.	Field · UnityEngine
[Min(value)]	Set an Inspector-side minimum for an int or float field.	Field · UnityEngine
[Max(value)]	Not a general built-in UnityEngine field attribute in the Unity 6 core API.	Optional package or custom drawer
[TextArea(min, max)]	Render a multiline text box with a height range in the Inspector.	Field · UnityEngine
[Multiline]	Show a string field as a multiline text field.	Field · UnityEngine
[Delayed]	Commit Inspector text or numeric edits on Enter or focus loss.	Field · UnityEngine
[SerializeReference]	Serialize managed object references, including supported polymorphic graphs.	Field · UnityEngine
[InspectorName("Name")]	Change the displayed Inspector label.	Field or enum member · UnityEngine
[ContextMenuItem("Title", "Method")]	Add a context-menu entry to a field which calls a method.	Field · UnityEngine
[NonReorderable]	Disable drag-to-reorder controls for an Inspector array or list.	Field · UnityEngine

How to choose

[SerializeField]

Make a private field part of Unity serialization and show it in the Inspector.

Use it when: Expose a tuning value while keeping access private.

Be aware: The type must meet Unity serialization rules. This does not expose a C# property.

Reference: Unity documentation

[HideInInspector]

Hide a serialized field from the Inspector without necessarily removing its saved data.

Use it when: Retain saved state that should not be adjusted by ordinary Inspector edits.

Be aware: Hiding a field is not the same as disabling serialization or making it secret.

Reference: Unity documentation

[NonSerialized]

Stop a public field from being serialized using the .NET attribute.

Use it when: Keep a public runtime cache out of scene and prefab data.

Be aware: Use [System.NonSerialized], not a UnityEngine attribute.

Reference: Unity documentation

[FormerlySerializedAs("oldName")]

Preserve serialized field values after a field is renamed.

Use it when: Rename a field in a component used by existing scenes and prefabs.

Be aware: Provide the previous serialized name and test old scenes, prefabs and assets.

Reference: Unity documentation

[Header("Title")]

Add a heading above a field in the Inspector.

Use it when: Visually divide settings for movement, audio or gameplay.

Be aware: Inspector presentation only; it does not group fields into a new serialized object.

Reference: Unity documentation

[Space] / [Space(n)]

Add vertical space before a field in the Inspector.

Use it when: Add a little breathing room between unrelated Inspector settings.

Be aware: Avoid using many Space attributes to replace sensible naming and grouping.

Reference: Unity documentation

[Tooltip("…")]

Show explanatory text when hovering a field label.

Use it when: Explain units or an unusual setting without cluttering the field name.

Be aware: Good for explaining units and expected values, not for replacing API documentation.

Reference: Unity documentation

[Range(min, max)]

Show a slider for an int or float field in the Inspector.

Use it when: Choose a speed, volume or other numeric setting with a bounded slider.

Be aware: This controls Inspector input, not arbitrary assignments made by code at runtime.

Reference: Unity documentation

[Min(value)]

Set an Inspector-side minimum for an int or float field.

Use it when: Avoid negative or zero values when editing counts and sizes.

Be aware: Validate or clamp runtime values separately.

Reference: Unity documentation

[Max(value)]

Not a general built-in UnityEngine field attribute in the Unity 6 core API.

Use it when: Only use when the installed package actually provides this attribute.

Be aware: Some third-party/Unity packages define similarly named attributes. Check the package namespace before using one.

Reference: Unity documentation

[TextArea(min, max)]

Render a multiline text box with a height range in the Inspector.

Use it when: Let designers enter descriptions or dialogue across several lines.

Be aware: The min/max arguments relate to visible lines, not a string length limit.

Reference: Unity documentation

[Multiline]

Show a string field as a multiline text field.

Use it when: Make a short multiline text field more convenient in the Inspector.

Be aware: For larger notes or a selectable height range, consider TextArea.

Reference: Unity documentation

[Delayed]

Commit Inspector text or numeric edits on Enter or focus loss.

Use it when: Avoid responding to every keystroke while editing numeric settings.

Be aware: It changes editing behavior, not the timing of assignments made by scripts.

Reference: Unity documentation

[SerializeReference]

Serialize managed object references, including supported polymorphic graphs.

Use it when: Store different concrete implementations behind an interface in a managed object graph.

Be aware: Not for UnityEngine.Object references. Concrete types must be serializable and supported.

Reference: Unity documentation

[InspectorName("Name")]

Change the displayed Inspector label.

Use it when: Show a friendly label while retaining a stable C# identifier.

Be aware: The C# identifier and serialization field name stay unchanged.

Reference: Unity documentation

[ContextMenuItem("Title", "Method")]

Add a context-menu entry to a field which calls a method.

Use it when: Offer an occasional field-specific reset or repair command.

Be aware: This is a field context menu, not a permanently visible button.

Reference: Unity documentation

[NonReorderable]

Disable drag-to-reorder controls for an Inspector array or list.

Use it when: Keep a fixed-order collection from being rearranged accidentally in the Inspector.

Be aware: The collection can still change in code.

Reference: Unity documentation

Inspector before and after

This illustration is an original, simplified mockup, not a screenshot of a specific Unity Editor version.

Without attributes

Player Settings

Speed5

Lives3

With Header, Range and Tooltip

Player Settings

Movement

Speed ⓘ

5

Lives3

A useful field setup

Unity C# | PlayerSettings.cs

using UnityEngine;
using UnityEngine.Serialization;

public sealed class PlayerSettings : MonoBehaviour
{
    [Header("Movement")]
    [Tooltip("Units per second")]
    [FormerlySerializedAs("moveSpeed")]
    [SerializeField, Range(0f, 20f)]
    private float speed = 5f;

    [SerializeField, Min(1)]
    private int lives = 3;

    public float Speed => speed;

    private void OnValidate()
    {
        // Inspector attributes alone do not validate every runtime assignment.
        speed = Mathf.Clamp(speed, 0f, 20f);
        lives = Mathf.Max(1, lives);
    }
}

The field remains private, but the Inspector can edit it. Other scripts receive read-only access through the property. OnValidate runs in the Editor; if values also arrive from runtime data, validate them at that entry point.

Runtime validation

Range and Min are not a substitute for validating values coming from gameplay, saved data or network input.

Related lessons

• Unity scripting lifecycle
• Assembly definitions
• Namespaces