I built the same app with Claude Design and its open-source rival, and the winner wasn't close

At a glance:

• Claude Design, Anthropic’s design tool launched in April 2026, costs $20 per month and generates real HTML/CSS/JS output.
• Open Design is a free, Apache‑2.0‑licensed desktop app that runs locally and lets you bring your own model (BYOK).
• In a side‑by‑side test the author found Claude Design’s editing experience far smoother, while both tools produced comparable designs.

What the tools are

Claude Design is Anthropic’s newest visual‑design assistant, bundled into the Claude Pro plan. It lives in the Claude tab next to chat, produces production‑ready HTML, CSS and JavaScript, and can export to Canva, PDF, PPTX or plain HTML. The service runs on Anthropic’s cloud and is locked to the company’s Opus models; the author used Opus 4.7 for the comparison.

Open Design positions itself as “the open‑source alternative to Claude Design”. It is a native desktop application released under the Apache‑2.0 license, runs locally on the user’s machine, and supports any OpenAI‑compatible endpoint via a bring‑your‑own‑key (BYOK) approach. The author tested it on an 8 GB VRAM setup using the same Opus 4.7 model accessed through a local Ollama server.

Testing methodology

Both tools were given the identical prompt: “Create a local LLM benchmark tracker with a sortable table, an add/edit form, runner filters, persistent storage, and a dark mode.” The prompt was deliberately small but layered, requiring the generation of a functional UI, theme handling, and interactive components. The author stripped the model out of the equation by using the same Opus 4.7 key in both environments, ensuring that any differences stemmed from the design editors themselves.

The evaluation focused on two dimensions:

1. Design output – visual fidelity, component layout, and export options.
2. Editing experience – responsiveness, context‑menu functionality, element movement, and overall usability during iterative tweaks.

Results for Claude Design

Claude Design produced a near‑perfect first‑generation UI. The author highlights:

• Warm amber accent, JetBrains Mono for numbers and Inter for body text, matching the “terminal‑leaning” aesthetic without extra prompting.
• A header stats row (model count, average tok/s, average TTFT, top performer) appeared automatically.
• Inline, collapsible add‑form with segmented controls for tool‑calling status and 1‑5 rating.
• Real‑time theme switching (amber, phosphor, mono, synth) via the “Tweaks” panel.
• Improved side‑panel stability, a functional color picker, and a full set of typography, padding, margin, and appearance controls.
• Right‑click now brings a proper context menu (copy, paste, group, wrap in flex, etc.).
• Element movement now works, though it snaps to the layout grid.

Overall, Claude Design felt more like a polished editor than a prototype, delivering both design quality and a smooth editing workflow.

Results for Open Design

Open Design also generated an impressive Discord‑style benchmark dashboard:

• Sidebar with channel‑style runner filters, a #benchmarks header, and a library‑stats card.
• Main table with correct columns, hover‑to‑edit/delete, and status dots (green/yellow/red).
• Polished edit modal mirroring Claude’s segmented controls.

However, the editing experience lagged behind:

• Clicking elements was laggy; the edit panel jumped around the screen.
• Selection often grabbed nearby or parent elements, requiring multiple attempts.
• When the edit panel finally appeared, interacting with it sometimes selected a different element in the design.
• The chat‑driven “move this to the bottom” command worked but consumed tokens, making it less efficient than a direct UI drag.

Open Design’s strengths lie in its extensibility: hundreds of built‑in skills, plugins, design systems, and a smart discovery questionnaire that tailors the UI to the chosen visual direction (the author selected a Discord theme).

Overall assessment

Both editors rely on Opus 4.7 for the heavy lifting, and the visual output was comparable. Claude Design’s cloud‑hosted model delivered a snappier, more reliable editing experience, while Open Design’s local‑only approach introduced latency and UI quirks despite its generous feature set and zero cost. For users who need a ready‑to‑use, polished editor and are comfortable paying $20 / month, Claude Design currently leads. Open Design remains a promising open‑source project, especially for developers who want BYOK flexibility and are willing to tolerate a rougher editing workflow.