Dia vs SigmaOS (2026): which should you pick?
As of Nov 12, 2026, SigmaOS grades higher than Dia: 2.4 against 2.0 out of 4.0.
Checked Oct 9, 2026 and Nov 12, 2026 · graded Oct 10, 2026 and Nov 12, 2026 by ToolGPA
Dia grades higher on features and platforms. SigmaOS grades higher on value for money and the free plan. They get the same grade on ease of use.
Price, platforms and features side by side. The table says where each price was read and when.
Dia
AI browser for work that answers questions across tabs and tools
SigmaOS
Mac browser with vertical tabs, workspaces and an AI assistant
Which one is for you
Pick Dia if
- Fits if your working day is spread over Slack, Notion, Google Workspace and Teams
- Works for people who want a daily brief and meeting notes pulled up before each call
Look elsewhere if
- Skip it if you want AI for free, as the free plan is the browser alone and chat starts on the paid plans
- Pricey if you want the Morning Brief and reports, which need Better Days at $100 a month
- Not for you if you browse on a phone or Linux, and on Windows the paid plans aren't live yet
- Watch out: the plan card says $10 a month for Better Answers while the FAQ on the same page says $20
- Tight if you use the AI a lot, since it pauses when your Tasks run out unless you buy $20 credit blocks
Pick SigmaOS if
- Fits if you live on a Mac and want tabs down the side in separate workspaces
- Works for people who want an assistant that answers questions about the page
Look elsewhere if
- Not for you if you use Windows or Linux, as it runs on macOS only
- Pricey if you want unlimited AI, which needs Pro at $20 a month
- Watch out: the help docs list an older Pro price of $10 a month, against $20 on the homepage
- Watch out: iOS and Windows versions are described as coming, and pages on the site carry a 2024 copyright notice
How we grade them
| 2.0GPADiaFair | 2.4GPASigmaOSFair | |
|---|---|---|
| Value for money | DThe Better Answers card says $10 a month, the top of what browsers charge, and the FAQ on the same page still says $20, so even Dia isn't sure. Worse, the parts people come for, the Morning Brief, the reports, the decks, need Better Days at $100 a month against a category middle of $8.33. | AThe Personal plan is described as free forever, so the browser costs nothing. Unlimited Airis needs Pro at $20 a month, which is where this category's dearest tenth starts. |
| Free plan and trial | CBetter Browser is free, with profiles, tab groups, split view, picture-in-picture, ad and tracker blocking and sync. It also has no AI whatsoever, which is the only reason anyone picks Dia, so that's a wall on day one. The 14-day card-free trial is the honest look. | BA free-forever plan one person could live on, with the AI helper limited rather than missing. |
| Features | BIt covers the browser job, and the AI chats on any page drawing on your open tabs and your Slack, Notion and Google Workspace, preps meetings with the agenda opened for you, and assembles reports and decks from it all. Paid plans don't reach Windows yet, though. | CWorkspaces, vertical tabs, search across tabs and an ad blocker. Unlimited AI use is Pro only, and the help docs list an older Pro price of $10 against the homepage's $20. |
| Ease of use | CNo rating on record. Tab groups get named for you and split-view layouts are remembered, but the AI is only worth anything once you've connected Slack, Notion, Google Workspace and Teams, and then there's the Tasks meter to keep an eye on. | CNo store rating on record. Workspaces, profiles and keyboard-first search take some learning. |
| Platforms and integrations | CDesktop and nothing else: macOS and Windows, no Linux, no phone app of any kind. It connects to Slack, Notion, Gmail, Calendar, Outlook, Teams, GitHub and Figma, but the paid plans aren't live on Windows yet. | DmacOS only. The FAQ says iOS and Windows support are coming. |
| Best for | an AI browser that reads across your work tools | a Mac browser with vertical tabs and an AI helper |
The GPA is the average of the five grades: an A is 4 points, an F is none. The full reasons are on each tool's page: Dia and SigmaOS. How we grade
Price against what you get
Dia starts at $10 a month and scores 2.3 out of 4 on features, ease of use and platforms. SigmaOS starts at $20 a month and scores 1.7.
Dia scores higher and starts $10 a month lower. Of the other browsers on the chart, 14 score higher than Dia for less, and 22 score higher than SigmaOS for less.
Features, ease of use and platforms, averaged
What paid plans start at, a month (each step along is roughly double) →
- The best score at each price
- Has a free plan
- No free plan
Where they differ
- Dia is end-to-end encrypted, according to its own site.
- Dia also covers chat assistant.
- SigmaOS also covers ad and tracker blocking.
At a glance
| Dia | SigmaOS | |
|---|---|---|
| Pricing | Free plan | Free plan |
| Starts at | $10 per month (Better Answers) | $20 per month (Pro) |
| Free plan | Better Browser: the browser with profiles and tab groups, split view, picture-in-picture video, a built-in ad and tracking blocker and cross-device sync, but no AI features. | SigmaOS Personal is described as free forever; unlimited Airis AI usage is a Pro feature. |
| Free trial | 14-day free trial of the Better Days plan for new users, no credit card required | None listed |
| macOS | ||
| Windows | ||
| Made by | The Browser Company of New York | SigmaOS, Inc. |
| Price read from | diabrowser.com | sigmaos.com |
| Checked | Oct 9, 2026 | Nov 12, 2026 |
Worth knowing
Dia
- The free Better Browser plan has no AI features; chat needs Better Answers at $10 per month, and the Morning Brief and reports need Better Days at $100.
- Paid usage is metered in Tasks. When the monthly allowance runs out, AI features pause unless extra usage is bought in $20 credit blocks.
- Dia is offered for macOS and Windows only. Paid plans began with new Mac users on August 17, and the FAQ says they do not yet apply on Windows.
- The plans page disagrees with itself: the Better Answers card shows $10 a month, while the FAQ further down the page still says $20.
SigmaOS
- It runs only on macOS; the FAQ says iOS and Windows support are coming.
- Unlimited Airis usage needs the paid Pro plan.
- The company's help docs list an older Pro price of $10 per month ($8 billed yearly); the homepage FAQ says $20 a month. Check the price in the app before buying.
- Pages on the site carry a 2024 copyright notice.
Key features
Dia
- Chat with context from tabs and tools
- On paid plans, a question asked on any page is answered using open tabs and connected tools such as Slack, Notion, Google Workspace and Microsoft Teams.
- Morning Brief
- A daily brief lays out the calendar, inbox and key links before the workday starts. It is part of the Better Days plan.
- Reports, decks and recaps
- Dia gathers context scattered across tools into a shareable report or a slide deck with headers and layout. These are part of the Better Days plan.
- Meeting prep
- Before a call, Dia opens the meeting page, agenda, notes and related documents and shows a countdown to the start time.
- Profiles, tab groups and split view
- Profiles keep work, freelance and personal tabs, logins and AI separate. Related tabs are grouped under descriptive names, and split view layouts are remembered.
- Privacy controls
- Ad and tracker blocking are built in, memory and chat personalization can be switched off, and synced data is end-to-end encrypted. Dia for Work adds SSO and admin tools.
SigmaOS
- Workspaces and vertical tabs
- Tabs are kept in separate workspace lists down the side of the window, and a workspace can use separate profiles to sign in to different accounts.
- Tabs as tasks
- Tabs can be marked as done when finished or locked to a workspace to keep them.
- Lazy Search
- Pressing the spacebar searches across open tabs, the web, commands and bookmarks.
- Airis assistant
- The AI companion can answer questions about the page you are on, search the web and read several pages at once, and a Simplify view summarizes a page.
- Ad blocker and Focus Mode
- A built-in ad blocker is included, and Focus Mode hides everything except the current page.
- Chromium extensions
- The FAQ says SigmaOS is a WebKit browser that also supports Chromium extensions.
Plans
Dia
Better Browser$0
The browser with no AI features: profiles and tab groups, split view, picture-in-picture video, ad and tracking blocking and cross-device sync.
Better Answers$10
per month on the plan card; the page's FAQ still says $20
Adds chat on any page with context from tabs and connected tools, within a monthly usage allowance measured in Tasks.
Better Days$100
per month
6x the usage of Better Answers, plus the daily Morning Brief, meeting prep and follow-up, and generated reports, decks and recaps.
SigmaOS
Personal$0
The browser for macOS, free, without unlimited Airis AI usage.
Pro$20
per month; billing basis not stated on the page
Unlimited Airis usage. The site says Pro starts at this price and gives students and educators 50% off.
Ways to pay less
Dia
No public discounts listed.
SigmaOS
- Education
50% off Pro for students and educators
The homepage FAQ says students and educators are eligible for a 50% discount on SigmaOS Pro.
Common questions
Which is cheaper, Dia or SigmaOS?
As of Nov 12, 2026, Dia is cheaper to start with: $10 a month, against $20 a month for SigmaOS. Dia starts at $10 per month (Better Answers), and SigmaOS starts at $20 per month (Pro).
Which has a free plan, Dia or SigmaOS?
As of Nov 12, 2026, both Dia and SigmaOS have a free plan.
Which platforms do Dia and SigmaOS run on?
As of Nov 12, 2026, only Dia lists a Windows app. Both list a macOS app. A platform missing from a listing is one its maker's pages did not mention.
More comparisons
How this page was made
- The verdict at the top follows a fixed rule. When both tools are in the same category and either is in our top three for it, the verdict follows that ranking: the higher-placed tool is our pick. The top three weigh who each tool suits as well as its grades, so a pick can go against the GPA. Otherwise the page does not pick one and says which grades higher: the higher GPA first; on a tie, the one with a free plan, then the one that starts cheaper in dollars a month, counted the same way for both; if they are still level, what the choice depends on.
- The grades are our own, from each tool’s review or report card. The GPA is their average.
- Prices, plans and platforms come from each tool’s listing. The table above says where each price was read and when.
- The differences and the answers to the questions are worked out from those listings.