The pitch for an agentic browser is the same from all four vendors: stop reading the web and let the browser do the web. Ask it to compare three vendors' pricing pages and it opens all three, extracts the numbers, and hands you a table. Ask it to reorder last month's supplies and it finds the cart, fills it, and stops one click short of checkout. In a two-person company where the founder is also the ops team, that is a real lever — the sort of grunt work that never justified a hire but quietly eats a morning.

So the useful question is not "are they good." It is which one belongs on your team's machines, and the answer turns out to have almost nothing to do with which model is smartest. The four sort cleanly by three things a founder actually has to live with: who pays, where your data lands, and how much authority you are handing an AI that cannot reliably tell your instructions from a stranger's.

The one-screen answer#

Everything below is the reasoning behind those four sentences.

Price and distribution: Comet changed the math#

Comet launched in July 2025 as a $200/month curiosity effectively locked behind Perplexity's top tier. That framing is dead. As of March 2026 Comet is free worldwide on iOS, Android, Windows, and Mac, with the headline agentic features intact; the only paid add-on is Comet Plus at $5/month for premium publisher content. For a founder, "free for the whole team, no seats to provision" is a materially different purchase than "$20/month per person before anyone has proven it saves time."

Atlas sits at the other end. The browser is a free download, but the part you actually want — Agent Mode — is gated to paid ChatGPT tiers: Plus at $20/month, or Pro/Business above it. That is not a dealbreaker if your team already pays for ChatGPT; it is the same subscription doing more work. It is a second budget line if they don't.

Gemini's advantage isn't price, it's inertia: it lives inside Chrome, and Chrome is ~65% of the market. Auto Browse is gated to Google AI Pro/Ultra, but the browser is already the default on most of your team's machines, so "adopting" it is closer to flipping a setting than migrating a tool. Dia, from the Arc team now owned by Atlassian, competes on feel rather than autonomy — a quieter, Chrome-like surface with ambient AI, aimed at people who found Arc too clever.

The decision nobody puts on the pricing page: blast radius#

Here is the part that should decide your pilot, and it is identical across all four vendors: an agentic browser fuses your authenticated session with untrusted page content in a single context, so the agent acts with your logged-in credentials on instructions that can be written by anyone whose text the page contains. That is not a bug queued for a patch. Brave demonstrated a hidden Reddit comment driving Comet to read a Gmail one-time passcode and leak it; Atlas was injectable within days of launch; and OpenAI itself now says prompt injection is unlikely to ever be fully solved. We covered why the flaw is structural in Why AI Browsers Still Can't Stop Prompt Injection — read it before you hand any of these an inbox.

The founder takeaway is not "don't use them." It is that the axis of comparison for real work is blast radius, not IQ. Rank the browsers by how much you let their agent do without a human in the loop, and match that to the task:

This is the same discipline you'd apply to any browser-automation agent: the credentialed action is the dangerous one, and the agent should never reach it from untrusted input without a gate.

How to actually pick#

Run a two-week pilot, not a migration. Put one browser in front of a small group, aimed at the low-risk column only, and measure whether it saves real time before you touch anyone's default:

  1. Default to Comet if cost and team-wide reach dominate — it's free, cross-platform, and needs no per-seat AI plan.
  2. Choose Atlas if your team already runs on ChatGPT and you want the agent to share that memory and history.
  3. Choose Dia if what you want is a calmer AI daily driver, not an autonomous operator.
  4. Choose Gemini in Chrome if "don't make the team switch browsers" outranks everything else and you already pay for Google AI.

Whichever you pick, the leash matters more than the logo. If you're building agent-driven browsing into a product rather than adopting one off the shelf, the framework-level tradeoffs are a different comparison — Browser Use vs Stagehand vs Playwright MCP is where that decision lives. But for the founder just trying to answer "what do we install," the four consumer browsers above split on price, data home, and how much rope you're comfortable giving them — and the smartest agent is worth nothing if you've handed it the keys to a page a stranger can write.