# ValueChecker

> Perceptually accurate value checker for artists, emulating Photoshop’s dot gain 20% profile.

Canonical page: [https://chrome-stats.com/d/valuechecker](https://chrome-stats.com/d/valuechecker)

## Overview

- **ID:** `valuechecker`
- **Platform:** Firefox
- **Type:** Firefox add-on
- **Status:** Available
- **Publisher:** akabi
- **Category:** appearance
- **Version:** 1.0
- **Last updated:** 2026-04-22
- **First published:** 2026-04-19
- **Size:** 214 KB
- **Data as of:** 2026-09-21
- **Store listing:** [Firefox Add-ons Store](https://addons.mozilla.org/firefox/addon/valuechecker/)
- **Website:** [https://github.com/akabisan/valuechecker](https://github.com/akabisan/valuechecker)

## Description

ValueChecker is designed for artists to check and analyze value structure of images, videos, and GIFs by emulating the working gray (dot gain 20%) profile found in Photoshop or Gray Gamma 1.8 in other software.

Standard grayscale filters/modes ignore how the human eye perceives brightness, leading to inaccurate results where bright colors can appear much darker than they should. This tool utilizes Rec. 709 luminance formula within a linear RGB color space to ensure the values remain perceptually accurate.

Press Ctrl+Y to toggle the add-on or customize it to your own liking.

## Rankings

- #138,094 — Overall
- #76 — value

## Permissions and access

### Permissions

- `storage`
- `activeTab`

### Content script matches

- `<all_urls>`

## Safety

- **Risk impact:** Moderate risk impact
- **Risk likelihood:** Moderate risk likelihood

### Analysis details

- Allows access to all websites, posing a significant security risk as it can monitor and modify data from any visited site.
- This extension has low user count. Unpopular extensions may not be stable or safe.

> Some risk analysis details are omitted from this free response. [Upgrade to view the full analysis](https://chrome-stats.com/pricing).

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Source: [Chrome-Stats](https://chrome-stats.com/d/valuechecker)