Sider AI

What people say

Sider remains one of the most widely installed AI browser sidebars, developed by Vidline Inc. (founded in Tokyo, now Boston-based). It holds an unusually strong rating on the Chrome Web Store — around 4.9 stars across more than 100,000 reviews — and the product has kept evolving: a 2025 overhaul added Deep Research agents and Wisebase, a personal knowledge base that automatically saves research reports, highlights and uploaded documents so you can chat with everything you have collected.

What users consistently praise is the convenience. Sider puts GPT, Claude and Gemini models one keystroke away on any web page, and reviewers repeatedly single out the page summaries, inline translation, email drafting and the ability to highlight text anywhere and act on it without switching tabs. For people who live in the browser, it genuinely collapses a dozen small copy-paste workflows into one panel.

The complaints are almost entirely about the billing model rather than the features. Sider runs on a credit system that many users find confusing: advanced models and agents consume credits at different rates, heavy use gets expensive quickly, and even the so-called unlimited plans carry a monthly cap on advanced credits that does not roll over. Some reviewers report frustrating refund experiences after hitting unexpected daily restrictions, and power users grumble that the sidebar offers little customisation — you cannot change its appearance, shortcuts or default model behaviour to any deep degree.

Sider fits students, researchers and knowledge workers who want one subscription covering multiple frontier models plus a tidy research workflow, and who will actually use the summarise-translate-write loop daily. If you already pay for ChatGPT or Claude directly and mostly need raw chat, the credit maths works against you; if your work is reading and synthesising web content all day, it earns its keep.

Summary of public user & expert reviews, compiled by RECATOOLS.