Warning

In the near future, Roblox is planning to patch local Fast Flag modification by utilizing the ClientSettings API for fetching the ClientSettings.json file. Probably the same reason why you can't change material textures locally now. As of 07/04/2024, Roblox has not yet forced the update through the Live channel.

Tutorial

Tip

Bloxstrap is highly recommended for modifying the Roblox client.

For Those Who Want to Use the Bloxstrap Flags Menu

1. Press [⊞+r]
2. Type %localappdata%/Bloxstrap/Bloxstrap.exe -menu
3. Click on FastFlags
4. Click on FastFlag Editor
5. Use common sense

Note

When adding Flags, it's best to remove the quotation marks around the Flag and value.

For Those Who Want to Modify the JSON Flags File

For Bloxstrap Users

1. Press [⊞+r]
2. Type %localappdata%/Bloxstrap/Modifications/ClientSettings/ClientAppSettings.json

For Roblox Users

1. Press [⊞+r]
2. Type %localappdata%/Roblox/Versions/ClientSettings/ClientAppSettings.json

Note

For every installation and update, Roblox clears the ClientSettings folder. It's best to keep a backup of your ClientAppSettings.json file. You may install Bloxstrap for automatic changes.

Modifying the JSON Flags File

3. Open ClientAppSettings.json or create a new .json file with the name ClientAppSettings
4. Follow this format:

{
	"Flag1": "Value1",
	"Flag2": "Value2"
}

More information about Flags here

Fast Flags

May this list serve as an in-depth explanation to different Flags you may have heard of but not familiar with its functionality. You may fork and send a pull request if you have any corrections / suggestions that deserves to be in this list.

• Graphics
• Physics
• Render
• User Interface
• Others
• Credits

Graphics

Network Interpolation Visualizer

false Highlights physically moving parts by pressing [ctrl+f8][ctrl+i].

Caution

This Flag is exploitable.

{
	"DFFlagDebugEnableInterpolationVisualizer": true
}

Quality Scale Fix

false Fixes blurry quality when your display scale is greater than 100%.

{
	"DFFlagDisableDPIScale": true
}

Set FPS Cap

0 Allows you to set your max FPS limit. However, unlike RFU's memory write mode, the set FPS limit cannot be changed later during the game.

Note

A more advanced Flag is available.

{
	"DFIntTaskSchedulerTargetFps": 144
}

Player Billboard

false Adds a black billboard and a red circle above and below every player, respectively.

Caution

This Flag is exploitable.

{
	"FFlagDebugAvatarChatVisualization": true
}

Display FPS

false Displays your FPS without pressing [shift+f5] and showing other details with the expense of not being able to toggle it.

{
	"FFlagDebugDisplayFPS": true
}

Exclusive Fullscreen

true Allows you to enter exclusive fullscreen mode by pressing [alt+enter]. Significantly improves performance, lowers input latency, with the expense of screen tearing.

Note

V-sync will be disabled upon entering exclusive fullscreen.

{
	"FFlagHandleAltEnterFullscreenManually": false
}

Physics

Noclip

30 Allows you to clip through thin walls / floors. The lower the number, the more the thickness of parts you can clip through.

Caution

This Flag is exploitable.

{
	"DFIntAssemblyExtentsExpansionStudHundredth": -30
}

Set Physics FPS Cap

16 Allows you to set the max physics limit, however it only goes above 15 and below 60 to literally prevent speed hacking. Setting it to 9223372036854776000 prevents the physics FPS from going below 60, useful to prevent slow-downs during FPS drops.

{
	"DFIntMaxMissedWorldStepsRemembered": 9223372036854776000
}

Fake Lag

15 Simulates high latency / desync as you will appear behind in the server than what it looks in the client.

{
	"DFIntS2PhysicsSenderRate": 1
}

Wall speeding

1 Controllable speed hack by gliding on long walls.

Caution

This Flag is exploitable.

{
	"DFIntUnstickForceAttackInTenths": -4
}

Render

Shadowmap Lighting Technology

false Forces future shadows but voxel lighting.

{
	"FFlagDebugForceFutureIsBrightPhase2": true
}

Future Lighting Technology

false Forces future shadows and lighting.

{
	"FFlagDebugForceFutureIsBrightPhase3": true
}

Voxel Lighting Technology

false Forces voxel shadows and lighting.

{
	"DFFlagDebugRenderForceTechnologyVoxel": true
}

Disable Direct3D 11

false Disables Direct3D 11 so you can use other 3D APIs.

{
	"FFlagDebugGraphicsDisableDirect3D11": true
}

Direct3D 10

false The client will use Direct3D 10 as the 3D rendering API.

Important

Requires the Direct3D 11 Flag to be disabled.

{
	"FFlagDebugGraphicsPreferD3D11FL10": true
}

Direct3D 11

false The client will use Direct3D 11 as the 3D rendering API.

{
	"FFlagDebugGraphicsPreferD3D11": true
}

OpenGL API

false The client will use OpenGL as the 3D rendering API.

Important

Requires the Direct3D 11 Flag to be disabled.

{
	"FFlagDebugGraphicsPreferOpenGL": true
}

Vulkan API

false The client will use Vulkan as the 3D rendering API.

Important

Requires the Direct3D 11 Flag to be disabled.

{
	"FFlagDebugGraphicsPreferVulkan": true
}

Fix / Force Blurry Textures

false 3 Do you have a sh*tty PC? Is Roblox forcing textures to look all slushy and distorted? No problem, this Flag controls all that! It allows you to set the quality of textures from 0 to 3, where 0 and 3 are the lowest and highest quality, respectively.

{
	"DFFlagTextureQualityOverrideEnabled": true,
	"DFIntTextureQualityOverride": 3
}

Low Mesh and Union Detail

250 500 2000 3000 Unions and meshes are composed of small polygons like triangles with the help of constructive solid geometry or CSG. This Flag lowers the detail and quality of CSG parts by reducing the amount of polygons rendered.

{
	"DFIntCSGLevelOfDetailSwitchingDistance": 0,
	"DFIntCSGLevelOfDetailSwitchingDistanceL12": 0,
	"DFIntCSGLevelOfDetailSwitchingDistanceL23": 0,
	"DFIntCSGLevelOfDetailSwitchingDistanceL34": 0
}

No Player Textures

8 Stops rendering every player's clothing, making them appear grey.

{
	"DFIntTextureCompositorActiveJobs": 0
}

Anti-aliasing

0 Sets the intensity of anti-aliasing by 0 (Default), 1, 2, 4, or 8. The higher the number, the more it may impact performance.

{
	"FIntDebugForceMSAASamples": 1
}

Set Light Updates _{by catb0x}

8 2 Limits light updates.

{
	"FIntRenderLocalLightUpdatesMax": 1,
	"FIntRenderLocalLightUpdatesMin": 1
}

No Shadows

75 Disables part and player shadows.

{
	"FIntRenderShadowIntensity": 0
}

No Post-Processing Effects

false Disables all post-processing effects like blur and depth-of-field.

{
	"FFlagDisablePostFx": true
}

User Interface

Hide Guis

4358041 Allows you to hide game Guis [ctrl+⇧+c], core Guis [ctrl+⇧+g], billboards [ctrl+⇧+b], and player names [ctrl+⇧+n].

Important

Requires you to be in a group.

Tip

Use with the Gui toggle Flag for best experience.

{
	"DFIntCanHideGuiGroupId": 32380007
}

No Chat

false Helps you focus on the game rather than having to deal with salty kids.

{
	"FFlagDebugForceChatDisabled": true
}

No Sound Drivers

false Disables Roblox from detecting audio output devices.

{
	"FFlagDebugRomarkMockingAudioDevices": true
}

2015 Gui

false false false The client will use the classic v1 Gui.

Important

Requires the 2024 Chrome Gui Flag to be disabled.

{
	"FFlagDisableNewIGMinDUA": true,
	"FFlagEnableInGameMenuControls": false,
	"FFlagEnableInGameMenuModernization": false
}

2020 Gui

false false false The client will use the v2 side bar Gui.

Important

Requires the 2024 Chrome Gui Flag to be disabled.

Note

Why is there no 2022 v3 Gui? Basically, v2 and v3 are the same Guis, it's just that the files Roblox used for handling the v3 Gui have been removed.

{
	"FFlagDisableNewIGMinDUA": false,
	"FFlagEnableInGameMenuControls": false,
	"FFlagEnableInGameMenuModernization": false
}

2023 Gui

false false false The client will use the modern v4 Gui.

Important

Requires the 2024 Chrome Gui Flag to be disabled.

{
	"FFlagDisableNewIGMinDUA": true,
	"FFlagEnableInGameMenuControls": true,
	"FFlagEnableInGameMenuModernization": true
}

No 2024 Gui

true true Roblox has since forced players to use the new Chrome Gui; these Flags disables it.

{
	"FFlagEnableInGameMenuChromeABTest2": false,
	"FFlagEnableReportAbuseMenuRoactABTest2": false
}

Advanced Graphics Quality

false Adds more quality bars from 10 to 21 bars.

{
	"FFlagFixGraphicsQuality": true
}

Set FPS Cap

false Allows you to set your max FPS limit in the Roblox settings by 30, 60, 144, or 240.

Important

Requires the target fps Flag to be set to 0 (Default).

{
	"FFlagGameBasicSettingsFramerateCap": true
}

Hide Guis

false false Allows you to toggle game Guis in the Roblox settings.

{
	"FFlagUserShowGuiHideToggles": true,
	"GuiHidingApiSupport2": true
}

Set Camera Zoom Limit

400 Allows you to set your camera's max zoom limit. Does not work on games with customized zoom limits.

{
	"FIntCameraMaxZoomDistance": 16384
}

No Roblox Blur Overlay

24 Disables the blur you see in loading and disconnection screens.

{
	"FIntRobloxGuiBlurIntensity": 0
}

Set Start Graphics Quality

-1 Allows you to set the graphics quality Roblox will always start with. Up to 10 by default, and up to 21 if the quality Flag is enabled.

{
	"FIntRomarkStartWithGraphicQualityLevel": 1
}

Others

Not What You're Looking For

false What are you doing?

{
	"DFFlagNotWhatYoureLookingFor": true
}

No Purchase Pop-up

false Disables in-game purchases.

{
	"DFFlagOrder66": true
}

No Ads

true Disables in-game ads and ad portals.

{
	"FFlagAdServiceEnabled": false
}

Force Lottery Win

false Makes you win every Roblox's lottery event.

{
	"FFlagDebugAnalyticsForceLotteryWin": true
}

Inhibit Roblox Data Collection

false false false false false false false Does not fully disable Roblox's telemetry system but stops most collection of user data.

{
	"FFlagDebugDisableTelemetryEphemeralCounter": true,
	"FFlagDebugDisableTelemetryEphemeralStat": true,
	"FFlagDebugDisableTelemetryEventIngest": true,
	"FFlagDebugDisableTelemetryPoint": true,
	"FFlagDebugDisableTelemetryV2Counter": true,
	"FFlagDebugDisableTelemetryV2Event": true,
	"FFlagDebugDisableTelemetryV2Stat": true
}

Bloxstrap Activity Tracking (Bloxstrap Only)

undefined Allows Bloxstrap to display information about the games you play, as well as enabling Discord Rich Presence for your profile.

{
	"FLogNetwork": 7
}

Credits

• Bloxstrap Discord
• Epic Fast Flags List
• Fast Flags Collection
• Fast Flags Collective :3
• Potato Flags
• Roblox FFlag Tracker