Mermaid Viewer vs Thumbnailr

A side-by-side comparison built from both listings. Blank cells mean the company has not given that detail; we never guess.

Mermaid Viewer compared with Thumbnailr
Detail	Mermaid Viewer	Thumbnailr
What it does	Free online Mermaid diagram viewer and editor with live preview, AI generation, and exports	Free YouTube thumbnail maker that runs in your browser, no sign-up or install required
Stage	Not given	Not given
Founded	Not given	Not given
Based in	Not given	Not given
Pricing model	Freemium	Freemium
Pricing	Free: unlimited editor and preview, 3 saved diagrams, 5 AI uses total, PNG export 1× with watermark. Starter: $6.99/month or $69.90/year; 30 saved diagrams, 500 AI conversations per month, PNG export up to 4× without watermark. Pro: $11.99/month or $119.90/year; unlimited diagrams, unlimited AI, PNG	Free mode: £0/forever with full editor, 10 templates, Thumbnail Check, feed test, series mode (3 per batch), 1280×720 PNG & JPG export, no watermark. Pro mode: £4.99/month or £39.99/year (about £3.33/month), includes 16 premium templates, brand kit, unlimited series (up to 200 per ZIP), one-click ba
Key features	Live preview of Mermaid code as you type AI diagram generator, editor and syntax fixer PNG export on every plan; JPG, SVG and PDF on Pro All 22+ Mermaid diagram types supported Share diagrams via public links and embeds Save diagrams to cloud with folders and version history Keyboard shortcuts and autocomplete Mobile-responsive editor with pan and pinch-zoom	10 free templates including 5 gaming layouts Bold outlined text and face cut-outs Thumbnail Check design checklist Feed test preview in mock social feed 1280×720 PNG and JPG export with no watermark YouTube video link import Works on desktop and mobile browsers Pro: one-click background removal on device Pro: 4K export and brand kit with saved colors and fonts
What makes it different	No account or sign-up required to start editing diagrams Affordable pricing: Starter at $6.99/month, Pro at $11.99/month Diagrams render in your browser; nothing stored unless you choose to save Fast editor with instant rendering and clear error messages	No sign-up or installation required, works directly in browser All images and projects stay private on your device, never uploaded Completely free with no watermark and no time limits 13 original gaming layouts with dedicated gaming pack
Community votes	0	0
DR (Domain Rating by Ahrefs)	6 +1 (up) since last check	Not checked yet no change since last check
Trust Flow (Majestic)	3	0
Citation Flow (Majestic)	23	0
Referring domains (Majestic)	12	0

5 details filled in for both companies.

More alternatives to Mermaid Viewer More alternatives to Thumbnailr