Skip to content
Back to the index

Ruler

mozilla.orgBrowser DevTools & extensions

PulseGate's liveness check found it on 12 Sep 2026; it is registered on Firefox Add-ons and has been in the index since 12 Sep 2026. How this is checked

Ruler is a Firefox browser extension that adds a horizontal ruler beneath the mouse cursor to help users follow long lines of text. It is activated with Ctrl+click and is intended for general Firefox users who want a simple reading aid.

Inferred · not functionally tested

FreeWebEmbeddablemacOSWindowsLinux
Ruler preview
Visit mozilla.org
1alternative
4features
2018since

Overview

4 features

Purpose: Reading long lines of text without losing your place.

Inferred · not functionally tested

Audience: Firefox users who need a visual reading aid

Inferred · not functionally tested

Functions: Unknown

Interfaces: API: unknown · MCP: unknown · CLI: unknown · Self-hosting: unknown

Recorded constraints: pricing: free · license: Proprietary · platforms: WEB · deployment: browser, embeddable, macos, windows, linux

Constraint provenance is unknown; confirm requirements with the publisher.

Record sources: addons.mozilla.org · addons.mozilla.org. These links do not verify the individual claims.

Ruler is a Browser DevTools & extensions project. Inferred · not functionally tested: It focuses on reading long lines of text without losing your place. Inferred · not functionally tested: Ruler is a consumer product aimed at firefox users who need a visual reading aid. Basis unknown · not verified: Ruler costs nothing to use. Basis unknown · not verified: It runs on the web, embeddable surfaces, macOS, Windows, and Linux.

Firefox user 13860642 builds and maintains Ruler, and it first shipped in 2018. Inferred · not functionally tested: Key capabilities include cursor ruler, ctrl+click activation, and reading aid. The interface is available in 32 languages, including Czech, German, and Greek.

Summary written by a language model from the project’s public pages.

Tasks: Inferred · not functionally tested

  • Cursor ruler
  • Ctrl+click activation
  • Reading aid
  • Long-line support

Topics: Inferred · not functionally tested

Tags
reading-ruleraccessibility-toolfirefox-extensiontext-reading

JSON profile · Text profile · Access guide

Built with & integrations

Runs on
BrowserEmbeddablemacOSWindowsLinux

Trust & compliance

Public signals
HTTPSPrivacy PolicyTerms of ServiceFree tierMulti-languageStore listing found
Legal
Privacy Policy Terms of Service

Indexing history

1

What PulseGate has recorded for this listing

  1. Indexed12 Sep · 06:11 UTC
    Ruler seen via Firefox Add-ons
    Source: Firefox Add-ons · Open

Frequently asked questions about Ruler

What is Ruler?
Inferred · not functionally tested: Ruler focuses on reading long lines of text without losing your place. It is catalogued under Browser DevTools & extensions on PulseGate.
Who should use Ruler?
Inferred · not functionally tested: Ruler is a consumer product built for firefox users who need a visual reading aid.
Does Ruler have a free plan?
Basis unknown · not verified: Yes — Ruler is free to use.
What platforms does Ruler run on?
Basis unknown · not verified: Ruler runs on the web, embeddable surfaces, macOS, Windows, and Linux.
Is Ruler still active?
PulseGate's liveness check found it on 12 Sep 2026.
What projects are similar to Ruler?
Similar projects tracked by PulseGate include Reading Ruler, Reading Helper Ruler, and Page Ruler.Reading RulerReading Helper RulerPage Ruler
Who makes Ruler?
Ruler is developed by Firefox user 13860642.
When did Ruler launch?
Ruler first shipped in 2018.

Similar projects

Closest matches by what these projects do