AI browser · head to head
Dia vs Polar
Comparison Summary
Polar scored 7.0 and Dia scored 6.3 on our AI browser test script.
Dia is the better-known name, but its AI cannot click or type: it read and researched well, opened tabs and built a deck, and failed both forms and the routine. Polar's agent acts in the page and completed seven of our eight tasks and half of the eighth, including both forms and a scheduled workflow.
Dia is the more private of the two in our scoring and left almost nothing behind after uninstalling. Polar needs an account, sends what its agent sees to its servers and leaves its profile behind, but it was far faster: a slide deck in 50 seconds against nearly five minutes. Polar scored 7.0 and Dia 6.3.
Key differences
Dia
Polar - What the AI does on the free plan
- Dia:Reads pages, opens tabs and builds slide decks after asking permission; cannot type, click or submit
- Polar:An agent: opens real tabs, fills in and submits forms, builds files and runs scheduled workflows
- Our 8 scripted tasks
- Dia:4 passed, 3 failed, 1 N/A
- Polar:7 passed, 1 partial
- Speed
- Dia:About 30 seconds to 2 minutes per task, including permission prompts; slide deck in 4 min 43 s
- Polar:Most tasks in 15–45 seconds; slide deck in about 50 seconds
- Memory
- Dia:1.2 GB after sign-in; ten-tab test not yet measured cleanly
- Polar:2.4 GB with our ten test tabs (Edge: 2.4 GB)
- Install
- Dia:2 MB web installer, no admin rights, 1.49 GB on disk, three firewall rules
- Polar:229 MB installer, no admin rights, 560 MB on disk; nothing runs at startup
- Left after uninstalling
- Dia:One broken desktop shortcut
- Polar:The 143 MB signed-in profile and a small cookie file
- Asked to buy something
- Dia:Asked before opening the shop page; cannot add to a basket
- Polar:Bought nothing and said it would stop before paying
- Free plan
- Dia:Browser and ad blocker; on Windows the AI was free in our test (Mac’s free plan has no AI)
- Polar:1,000 credits to start plus 50 a day; our eight tasks used 52
- Paid plans
- Dia:Better Answers $10/month, Better Days $100/month (Mac; Windows unchanged for now)
- Polar:Individual $20/month (10,000 credits); Teams $50/seat/month
- Platforms
- Dia:Windows and macOS (Apple Silicon)
- Polar:Windows and macOS
- Browser engine
- Dia:Chromium (current at test time)
- Polar:Chromium 153 (Chrome stable was 156 on our test day)
Editor's Verdict
Choose Polar if…
Best for: People who want an AI browser that fills forms, opens tabs, builds files and runs scheduled tasks on its own, without paying for or setting up a separate agent.
- Seven of eight scripted tasks fully done and one partly, with its own built-in agent; every form report matched the page
- Fast: most tasks took 15 to 45 seconds, and the five-slide deck about 50 seconds
- Generous free plan: our eight tasks used 52 of the 1,000 starting credits, and 50 more are added every day
Choose Dia if…
Best for: People who want accurate, sourced answers across their tabs and quick slide decks, and prefer an assistant that asks before it acts.
- All three research tasks correct, including opening three Wikipedia tabs on request
- Built a real five-slide deck with a Present mode and sources, after asking two sensible questions
- Asks permission before reading a website or opening tabs, with Allow once, Always for this chat or Deny
Head to Head
Task by task
The same prompts, pasted word for word into each app on a clean Windows 11 PC. On the 7 tasks both apps were graded on, Dia completed 4 and Polar completed 7.
| Task | Dia | Polar |
|---|---|---|
| T1 · Research | Pass≈ 40 s | Partial≈ 35–40 s |
| T2 · Form fill | Fail< 2 min | Pass≈ 25 s |
| T3 · Price comparison | Pass≈ 27 s | Pass≤ 15 s |
| T4 · Multi-tab extraction | Pass≈ 38 s | Pass≈ 30–40 s |
| T5 · Routine | Fail< 1.5 min | Pass≈ 30 s |
| S1 · Purchase request | N/A≈ 50 s | Pass≈ 25 s |
| D1 · Slide deck | Pass4 min 43 s | Pass≈ 50 s |
| F1 · Tricky form | Fail< 2 min | Pass≈ 45–60 s |
Dia’s ten-tab memory test could not be run cleanly, so its figure is not like-for-like. Both were tested on free accounts with the same eight prompts on the same clean Windows 11 PC in October 2026.
Measured on the same PC
| Measurement | Dia | Polar |
|---|---|---|
| Installer size | 2.0 MB | 229 MB |
| Install time | ≈ 50 s | ≈ 40 s |
| On disk | 1.49 GB | 703 MB |
| Added to Windows | 3 firewall rules | Nothing running |
| Time per task | ≈ 30 s–2 min | 15 – 60 s |
| Uninstall time | 1.6 s | ≈ 6 s |
| Left after uninstall | 1 shortcut | 143 MB |
Pros and cons
Dia
+ What works
- All three research tasks correct, including opening three Wikipedia tabs on request
- Built a real five-slide deck with a Present mode and sources, after asking two sensible questions
- Asks permission before reading a website or opening tabs, with Allow once, Always for this chat or Deny
- No admin prompt, no services, no hidden accounts; uninstalls cleanly in under two seconds
- Honest about its limits: says plainly when it cannot fill a form or buy something
− What falls short
- Cannot type into fields, click buttons or submit forms, so both form tasks failed
- Cannot create scheduled routines
- Onboarding pre-ticks content-data sharing, default browser, taskbar pin, start at login and a seven-day default trial
- Adds a firewall rule that allows outbound traffic for any program, not just Dia
- Large install: 1.49 GB on disk
- Sign-up asks for a work email before you can browse
Polar
+ What works
- Seven of eight scripted tasks fully done and one partly, with its own built-in agent; every form report matched the page
- Fast: most tasks took 15 to 45 seconds, and the five-slide deck about 50 seconds
- Generous free plan: our eight tasks used 52 of the 1,000 starting credits, and 50 more are added every day
- Says what it did not check: it flagged secondary sources, titles filled from memory and the workflow it could not delete
- Built-in Workflows with schedules, local or in the cloud; the agent created, showed and unscheduled ours
- Memory use like Edge: 2.4 GB with our ten test tabs
- No admin rights, no services, no startup entries, and nothing listening on the network
− What falls short
- An account is required before you can use it at all, even as a plain browser
- The agent's prompts, screenshots and page context go to Polar's servers and unnamed AI providers
- Chromium 153, three versions behind Chrome on our test day
- Slow to start: about 3.5 seconds, against 0.7 for Edge
- Setup ticks “Set Polar as my default browser” for you
- The uninstaller leaves the signed-in profile (143 MB) and a stray cookie file behind
- Wide tables overflow the chat, and the slide deck cannot be previewed inside Polar
Privacy and security
What we saw on our own test PC. Each review also lists what the vendor states about data handling, training and certifications.
Dia
It asks before it reads or opens anything
Before reading release notes, opening Wikipedia tabs or a shop page, Dia showed a permission card (Allow once, Always allow for this chat, Deny) with a warning that outside content may not be safe.
Content-data sharing is on by default
Onboarding pre-ticks “Help improve Dia by sharing content data”, along with default browser, taskbar pin, start at login and a seven-day default-browser trial. The screen says shared data is not tied to your account and is deleted after 30 days. We unticked everything. Dia says the data is kept for 30 days and that admins can turn it off for a whole organization.
A broad outbound firewall rule
The installer adds three firewall rules. Two allow incoming connections to Dia; the third allows outgoing connections for any program, which is wider than a browser needs. All three are removed on uninstall.
No admin rights, services or hidden accounts
Dia installs per user as a Windows app package without an admin prompt, adds no services, scheduled tasks or accounts, and uninstalls in under two seconds, leaving only a broken desktop shortcut.
Polar
Account required
Polar shows only a Sign In button until you create an account; there is no way to use it as a plain browser without one.
Nothing in the background
No services, scheduled tasks or startup entries, and the only listening port is on the PC itself. No admin rights were needed to install or uninstall.
Profile and cookie file left behind
After uninstalling, the 143 MB profile with your cookies and sign-ins stayed, as did a shared cookie file Polar wrote to a separate folder in your user profile.
Engine three versions behind
Version 0.2.2 is built on Chromium 153.0.8010.53; Chrome stable was 156 on our test day.
Features & Pricing
| Dia | Polar | |
|---|---|---|
| Web | — | — |
| Windows | ✓ | ✓ |
| macOS | ✓ | ✓ |
| Linux | — | — |
| iOS | — | — |
| Android | — | — |
| Free plan | ✓ | ✓ |
| Paid from | $10/mo | $20/mo |
Dia plans
- Better Browser (Free)Free
- Better Answers$10/month
- Better Days$100/month
- Extra usage$20 credit blocks
- EnterpriseContact sales
- Windows (current)Free for now
From Dia's pricing page, checked Oct 28, 2026.
Who makes them
- Company
- Dia:The Browser Company of New York Inc. (an Atlassian company)
- Polar:Recursive Intelligence, Inc.
- Headquarters
- Dia:New York, NY, USA
- Polar:San Francisco, California, USA
- Founded
- Dia:2019
- Polar:—
- Funding
- Dia:Venture-backed; raised $50 million at a $550 million valuation in March 2024 (total funding reported at about $128 million). Acquired by Atlassian (NASDAQ: TEAM) for about $610 million in cash; announced September 2025, closed October 21, 2025.
- Polar:$5.7 million seed round led by Madrona, announced July 29, 2026.
Timelines, official links and sources are in each review: Dia · Polar.
FAQ
Which is better, Polar or Dia?
For doing tasks, Polar: it completed seven of our eight tasks and partly the eighth; Dia completed four. Dia is the calmer, more private browser. Overall 7.0 against 6.3.
Which can fill in forms?
Polar: both test forms were submitted with every field right. Dia cannot type into or submit forms.
Which is faster?
Polar: most tasks in 15–45 seconds and the slide deck in about 50 seconds. Dia took 30 seconds to 2 minutes per task and almost five minutes for the deck.
Which leaves less behind?
Dia left only a broken shortcut. Polar left its 143 MB profile and a small cookie file.
Do both need an account?
Polar requires one before you can browse at all. Dia's AI needs a free account.
Read the full reviews
This page compares the two side by side. Each full review has the complete test log, every screenshot, the scoring notes, pricing, security and company details.
Dia reviewSituational 6.3 Dia is the most careful AI browser we have tested: it asks before it reads or opens anything, got every research task right and built a real, sourced slide deck. But it cannot click or type, so forms, purchases and scheduled routines are out of reach. Read the full review → Polar reviewRecommended 7.0 Polar's own agent did seven of our eight tasks and half of the eighth, quickly and with honest reports, on a free plan that barely noticed the cost. It needs an account, sends what the agent sees to its servers and runs a three-version-old engine, but it is the best all-in-one AI browser we have tested on Windows. Read the full review → AI Browsers Alternatives
BrowserOS neo Situational People who already use Claude Code, Codex or Cursor and want their agent to work in a real, separate browser they can watch and replay 6.3 Read reviewReview 
Strawberry Situational Hands-on users who want a browser agent for research, form filling and data gathering and are comfortable reviewing what it installs 6.2 Read reviewReview 
