How do their growth rates compare?

Explain Selected has a month-over-month growth rate of —; Sider has -10.6%.

How does pricing compare?

Explain Selected: Free. Free. The extension is offered at no cost in the Chrome Web Store, with no in-app purchases listed. Sider: Freemium. Freemium. Free tier available with limited credits; paid plans advertised at roughly US$10/month for occasional use up to around US$100/month at the top tier, with higher credit allowances and a dedicated cloud computer on the upper plans.

What are alternatives to Explain Selected and Sider?

Other tools in related categories include ChatGPT, Claude, Monica, Language Reactor, Merlin AI.

Head-to-Head Benchmark

Explain Selected vs Sider

Explain Selected records 0 monthly visits with — month-over-month growth and Free pricing. Sider records 2,644,740 monthly visits with -10.6% growth and Freemium pricing.

Explain SelectedFree

Highlight any text, get the right definition and a plain-language explanation

Monthly Visits

0

MoM Velocity

—

Top Market

🌐 Global

View Explain Selected Analysis

chromewebstore.google.com

SiderFreemiumTraffic Leader

AI sidebar and browser agent for reading, writing and research

Monthly Visits

2.64M

MoM Velocity

-10.6%

Top Market

🇺🇸 United States

View Sider Analysis sider.ai

Side-by-Side Traffic & Specification Matrix

Dimension / Metric	Explain Selected	Sider
Official Domain	chromewebstore.google.com	sider.ai
Pricing Model	Free	Freemium
Monthly Visits	0 (0)	2.64M (2,644,740)

Primary Market & Share	🌐 Global (—)	🇺🇸 United States (13.3%)

Direct Visits / mo	0	1.7M

User Rating	3.8	4.5

Supported Platforms	Browser Extension	Website

Explain Selected

Highlight any text, get the right definition and a plain-language explanation

Context-aware definitions

ChatGPT infers which sense of a word fits the sentence you highlighted, instead of dumping every dictionary entry at once.

Merriam-Webster definitions and audio

Matching dictionary entries and audio pronunciation are pulled in so you can hear as well as read the word.

One-click purple circle

Select text and click the purple circle that appears — no popup windows, no copy-pasting into a separate tab.

Personal saved list

Add words you want to remember to a personal list so you can review them later.

Strengths & Pros

+Resolves ambiguous words by using the surrounding sentence rather than guessing
+Combines AI explanations with established Merriam-Webster definitions and audio
+Works inline on any web page with a single click and no context switching
+Saving and sharing selections make it useful for building vocabulary over time

Limitations

Frequently Asked Questions: Explain Selected vs Sider

Explain Selected has 0 monthly visits, while Sider has 2,644,740. Traffic estimates describe audience size, not product quality.

More Head-to-Head Matchups

ChatGPT vs Explain Selected

6.05B visits/mo

ChatGPT vs Sider

6.05B visits/mo

Claude vs Explain Selected

1.25B visits/mo

Claude vs Sider

1.26B visits/mo

Explain Selected vs Monica

4.51M visits/mo

Monica vs Sider

7.16M visits/mo

Best Alternatives to Explain Selected & Sider (12)

Sider

AI sidebar and browser agent for reading, writing and research

AI sidebar on any page

A persistent panel that reads the page you are on and answers follow-ups with GPT, Claude or Gemini without copying content into another tab.

Summarise and chat with documents

Summarise long articles, PDFs and YouTube videos, extract key points, and ask detailed questions about the source material.

Translation and read-aloud

Translate webpages, PDFs and images, compare bilingual output side by side, and have content read aloud for review on the move.

Sider Hand browser agent

Delegate multi-step tasks across real websites — price comparison, form filling, research and inbox triage — using your existing logged-in sessions.

Strengths & Pros

+Works inside the browser you already use, with no context switching
+Access to multiple frontier models from one subscription
+Strong reading toolkit: PDF chat, YouTube summaries, translation and read-aloud
+Increasingly capable agent features for multi-step browser tasks

Limitations

–Useful credits run out quickly on the free and lower tiers

–Model availability and quota rules change over time, so expectations must be checked per plan

–Some agent and code features depend on a cloud machine and heavier plans

01

ChatGPT

6B/mo

SpecialistOpenAI's flagship multimodal assistant powered by GPT-6 and GPT-5.6 for reasoning, coding, and deep research.

AI ChatbotFreemium+2.2%

02

Claude

1.3B/mo

SpecialistAnthropic's frontier AI workspace powered by Claude 5.5 for agentic coding, analysis, and nuanced writing.

AI AssistantFreemium+23.8%

#2

03

Monica

4.5M/mo

Offers a very similar browser sidebar experience with multiple AI models, but features slightly different pricing and workspace tools.

AI AssistantFreemium55% direct

Monica web app showing an AI chat conversation with model selector and sidebar tools

#3

04

Language Reactor

1.9M/mo

Learn languages from Netflix, YouTube, and real-world texts with dual subtitles and AI

AI Language LearningFreemium+0.6%

05

Merlin AI

1.4M/mo

Provides robust browser-based summarization and prompt assistance, but lacks some of Sider's deeply integrated multi-model chat UI features.

AI AssistantFreemium+13.1%

Merlin AI Chrome extension sidebar summarizing a webpage

06

HARPA AI

537.5K/mo

Excels at advanced web automation and data extraction alongside chat, but has a steeper learning curve than Sider.

AI AgentFreemium+99.3%

HARPA AI extension panel showing model selection and page-aware prompt shortcuts on a website

07

Glarity

188.8K/mo

Free / Open-sourceSummarize YouTube, Google, and any page with AI — free in your browser

AI SummarizerFreemium7% direct

Screenshot of Glarity summarizing a YouTube video with timestamped highlights in the sidebar

08

Kome AI

174.9K/mo

Integrates bookmark management and content composition into a clean sidebar, but has a more limited feature set than Sider.

AI SummarizerFreemium30% direct

Kome AI extension summarizing a long article and saving it to the bookmark library

09

Voilà AI assistant browser extension overlay showing chat, writing and summarise options

Voilà — AI Assistant, Chat and Writer

152.2K/mo

Delivers streamlined inline writing and webpage summarization via a browser extension, but with fewer custom sidebar tools.

AI AssistantFreemium45% direct

Voilà — AI Assistant, Chat and Writer interface preview

10

CastReader

56K/mo

Read aloud webpages, PDFs, Kindle books and AI answers with synced highlighting

AI Text-to-SpeechFreemium+9.8%

CastReader browser extension reading a webpage aloud with the current word highlighted and Read & Explain annotations on screen

11

Voice Out

39.7K/mo

Turn any webpage, PDF, Doc or ebook into natural-sounding speech in 60+ languages

AI Text-to-SpeechFreemium71% direct

Voice Out browser extension showing a webpage being read aloud with speed controls and a voice picker

12

Quiz Solver AI

35.2K/mo

AI browser extension that reads quiz questions and answers them with explanations

AI QuizzesFreemium, Paid+28.6%

Quiz Solver AI extension panel showing an AI answer with step-by-step explanation on a quiz page

#1

Visit

ChatGPT

6B/mo+2.2%

Official

SpecialistOpenAI's flagship multimodal assistant powered by GPT-6 and GPT-5.6 for reasoning, coding, and deep research.

AI Chatbot73% direct

Freemium

Visit

Claude

1.3B/mo+23.8%

Official

SpecialistAnthropic's frontier AI workspace powered by Claude 5.5 for agentic coding, analysis, and nuanced writing.

AI Assistant72% direct

Freemium

Visit

Monica

4.5M/mo

Offers a very similar browser sidebar experience with multiple AI models, but features slightly different pricing and workspace tools.

AI Assistant55% direct

Freemium

Visit

Language Reactor

1.9M/mo+0.6%

Learn languages from Netflix, YouTube, and real-world texts with dual subtitles and AI

AI Language Learning77% direct

Freemium

Visit

Merlin AI

1.4M/mo+13.1%

Provides robust browser-based summarization and prompt assistance, but lacks some of Sider's deeply integrated multi-model chat UI features.

AI Assistant50% direct

Freemium

Visit

HARPA AI

537.5K/mo+99.3%

Excels at advanced web automation and data extraction alongside chat, but has a steeper learning curve than Sider.

AI Agent76% direct

Freemium

Visit

Glarity

188.8K/mo

Free / Open-sourceSummarize YouTube, Google, and any page with AI — free in your browser

AI Summarizer7% direct

Freemium

Visit

Kome AI

174.9K/mo

Integrates bookmark management and content composition into a clean sidebar, but has a more limited feature set than Sider.

AI Summarizer30% direct

Freemium

Visit

Voilà — AI Assistant, Chat and Writer

152.2K/mo

Delivers streamlined inline writing and webpage summarization via a browser extension, but with fewer custom sidebar tools.

AI Assistant45% direct

Freemium

Visit

CastReader

56K/mo+9.8%

Read aloud webpages, PDFs, Kindle books and AI answers with synced highlighting

AI Text-to-Speech35% direct

Freemium

Visit

Voice Out

39.7K/mo

Official

Turn any webpage, PDF, Doc or ebook into natural-sounding speech in 60+ languages

AI Text-to-Speech71% direct

Freemium

Visit

Quiz Solver AI

35.2K/mo+28.6%

AI browser extension that reads quiz questions and answers them with explanations

AI Quizzes66% direct

Freemium, Paid

Explain Selected vs Sider

Side-by-Side Traffic & Specification Matrix

Explain Selected

Strengths & Pros

Limitations

Frequently Asked Questions: Explain Selected vs Sider

How do Explain Selected and Sider compare in monthly traffic?

How do their growth rates compare?

How does pricing compare?

What are alternatives to Explain Selected and Sider?

More Head-to-Head Matchups

Best Alternatives to Explain Selected & Sider (12)

Sider

Strengths & Pros

Limitations