Comparisons
Sizzy compared with Polypane, Responsively, and Blisk
Three side-by-side comparisons of developer browsers and responsive testing tools, written from each vendor's public documentation. Every table marks what the vendor documents, and links to the source so you can check it.
Facts checked on 20 October 2026. Feature rows come from each vendor's public docs; pricing comes from each vendor's pricing page.
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What each tool is built around
Short version: Polypane for audits across viewports, Responsively for free device previews, Blisk for a Chromium browser with device sets, and Sizzy for the project workspace around the previews.
Sizzy vs
Polypane
Pick Polypane if accessibility and page-quality audits across many viewports are the centre of your workflow. Pick Sizzy if you want a project-first browser with isolated per-device sessions, a unified console and API client, terminals, and coding agents. Sizzy is $15/month with a 14-day trial; Polypane lists a 14-day trial and an Individual plan from €9/month billed yearly.
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Sizzy vs
Responsively App
Pick Responsively if you want a free, open-source device previewer and nothing else. Pick Sizzy if you want previews inside a full project workspace with isolated per-device sessions, a console and API client, terminals, and coding agents. Sizzy is $15/month with a 14-day trial; Responsively is free.
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Sizzy vs
Blisk
Pick Blisk if you want a Chromium browser that adds emulated device panes, per-device DevTools, and device sets with little setup. Pick Sizzy if you want project workspaces, isolated sessions per device, a unified console and API client, terminals, and coding agents. Sizzy is $15/month with a 14-day trial; Blisk lists a Premium license at $11.99/month.
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Method
How these pages are written
No ratings, no invented numbers, no user counts.
Each table row was checked against the vendor's own docs and pricing page on 20 October 2026. The comparison pages link to every page used.
A mark of Yes means the vendor documents it. Partial means the vendor covers part of the workflow, or documents it only for some cases. Not documented means we could not find it in the vendor pages we checked. It is not a claim that the feature is missing.
These are Sizzy's own comparison pages. We try to be fair, but you should assume we know our product best. Vendors change their products and prices, so open their pricing page before you buy.
Questions
Questions about the comparisons
Each page was written from the vendor's own public product docs and pricing page on 20 October 2026. Features the vendor does not describe are marked "not documented" rather than assumed to be missing.
No. These are Sizzy's own comparison pages, so they are naturally written from Sizzy's point of view. Every row links back to the vendor's documentation so you can check it yourself.
Sizzy is $15/month, $144/year (about $12/month), or $499 once for lifetime access. Every plan starts with a 14-day free trial and no credit card.
Keep comparing
The other comparisons
Each page follows the same structure, so you can read the same rows across every vendor.
Overview
All comparison pages
How these pages are written, and what each vendor is best at.
Polypane
Sizzy vs Polypane
Sizzy vs Polypane, compared from both vendors' public docs on 20 October 2026: viewports, sessions, accessibility audits, pricing, and when to pick each.
Responsively App
Sizzy vs Responsively App
Sizzy vs Responsively App, compared from both vendors' public docs on 20 October 2026: device previews, MCP support, sessions, workspaces, and pricing.
Blisk
Sizzy vs Blisk
Sizzy vs Blisk, compared from both vendors' public docs on 20 October 2026: emulated devices, DevTools, sync, sessions, workspaces, pricing, and agents.