A simple, open-source web tool to calculate the optimal Middle Grey (Paper White) and Contrast settings for the NVIDIA RTX HDR overlay based on your monitor's peak brightness.
GitHub Repository: Wootehfook/unofficial-rtx-hdr-calculator
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Live Demo: https://wootehfook.github.io/unofficial-rtx-hdr-calculator/
NVIDIA's RTX HDR filter uses specific sliders (Middle Grey, Contrast, Saturation) that can be confusing to calibrate. This calculator uses industry-standard math (ITU-R BT.2408) to determine the mathematically correct settings for your specific display, ensuring you preserve dynamic range without crushing blacks or blowing out highlights.
- Calibration Style: Choose Cinema / Reference (BT.2408) or Vivid / Daylight (BT.2100 HLG) based on room lighting.
- Target Gamma: Pick Gamma 2.0, 2.2, or 2.4 for your preferred shadow depth.
- Game Overlay Settings: Outputs Peak Brightness, Middle Grey, Contrast, and Saturation values.
- Profile Inspector (HEX): Shows 32-bit values for NVIDIA Profile Inspector entry.
- Live Updates: Real-time calculation as you type or adjust settings.
- Windows 11 Guide: Includes critical setup tips for Windows 11 (25H2) to prevent double-tone-mapping conflicts.
- Privacy Focused: Runs 100% client-side. No user data is stored or transmitted.
- Download
index.htmlor visit the live demo. - Enter your monitor's Peak Brightness (e.g., 1000 nits).
- Select your Calibration Style and Target Gamma.
- Copy the resulting values into the NVIDIA App Overlay (
Alt+Z-> Game Filter -> RTX HDR).
For users who prefer to configure RTX HDR via NVIDIA Profile Inspector (NPI), the calculator provides pre-converted 32-bit unsigned hexadecimal values. These values can be copied directly using the clipboard buttons next to each field.
Important: The hex values automatically account for NPI's internal +100 offset on the Contrast setting. For example, if the overlay shows 25% contrast, NPI requires a value of 125 (0x0000007D). The calculator handles this conversion automatically—do not apply any additional offset. Simply copy and paste the displayed hex values as-is.
To ensure RTX HDR works correctly without a "washed out" look, you must prevent conflicts with Windows' native features:
- Disable Auto HDR:
Settings > System > Display > HDR > Auto HDR [OFF] - Disable ACM:
Settings > System > Display > Advanced Display > Automatically manage color [OFF] - Note: The Windows "SDR Content Brightness" slider does not affect RTX HDR. If it does, RTX HDR is not active.
This project is based on community research and established standards. Sources are linked below for transparency and verification.
- Community Research: RTX HDR Paper White & Gamma Reference Settings by u/defet_ (r/nvidia).
- Standards:
- Report ITU-R BT.2408-8 (11/2024): Guidance for operational practices in HDR television production — Determines the "Reference" Paper White level (203 nits) and interpolation logic for lower brightness displays (Cinema mode).
- Recommendation ITU-R BT.2100-3 (02/2025): Image parameter values for high dynamic range television for use in production and international programme exchange — Contains the HLG System Gamma formula (Table 5, Note 2) which scales brightness based on display peak luminance (Vivid mode). (Note: If unavailable in your region, the previous standard BT.2100-2 (2018) contains the identical gamma formula.)
This website and calculator were built with the assistance of AI tools. While efforts have been made to ensure accuracy, please verify calculations and settings independently before applying them to your RTX HDR settings. The mathematical formulas used are based on industry standards, but edge cases or unusual display configurations may produce unexpected results.
Unofficial Project. This software is a fan-made tool and is not affiliated with, endorsed by, or connected to NVIDIA Corporation.
- "NVIDIA", "GeForce", and "RTX" are trademarks and/or registered trademarks of NVIDIA Corporation.
- All calculations are provided "as is" for educational and calibration purposes.