DMC 791 to Cosmo: Thread Conversion
The closest Cosmo equivalent to DMC 791 (Very Dark Cornflower Blue) is Cosmo 665.
Close MatchHex #464563 · blues family
This Cosmo conversion is based on approximate data that has not been independently verified. If you notice an error, let us know — community corrections help everyone.
Only the DMC swatch is rendered as stored color data here. Compare the physical target skein before you assume a visual match.
Affiliate links — we may earn a small commission at no cost to you.
Conversion Notes
Cosmo 665 is a close match for DMC 791 Very Dark Cornflower Blue. For designs where 791’s specific purple-blue warmth is important — floral work with violet or indigo themes where the warmer blue reads as part of the purple flower family, folk art designs where the cornflower blue family provides a key palette element — the exact-rated brand equivalents are preferable to Cosmo 665. The close rating at this deep, saturated value is particularly meaningful for palette-critical applications: a close substitute that drifts toward a cooler, more purely blue tone will shift the character of the thread from cornflower-blue to near-navy in the stitched piece. For applications where 791 is simply providing a deep blue shadow tone without hue-specific requirements — generic dark blue backgrounds, shadow accent positions in non-floral designs — Cosmo 665 is an adequate alternative. Cosmo’s slight silky finish can give deep blues a slightly more luminous quality in display conditions, which may be an advantage in fantasy pieces where the otherworldly quality of the blue-violet is part of the design’s appeal. For small-quantity accent use in folk art and band sampler designs, the close match is workable without critical testing.
Reference quality
How We Validate This Match
This Cosmo page is meant to help you shortlist a replacement quickly, then verify the physical skein before you mix brands in the same stitched area.
- Methodology
- This comparison uses the site's source-of-truth record for DMC 791, the stored Cosmo equivalent, and the saved close rating before rendering the page copy.
- Verification status
- Close cross-brand match. Treat it as a shortlist, not proof that the physical threads will be visually identical under every fabric and light condition.
- Source basis
- Approximate cross-brand floss mapping. Treat it as lower-confidence until you compare the physical Cosmo skein against the DMC reference.
- Last reviewed
- 2026-04-20
- Best use
- Close and approximate matches work best for replacements, backups, or whole-project brand swaps after you stitch a small sample on the target fabric.
Decision guide
When to trust DMC 791 to Cosmo 665
This page is strongest as a decision aid, not as a guarantee that two branded skeins will vanish into each other without testing.
Best for
- + Replacing missing floss when DMC 791 is unavailable and Cosmo 665 is good enough after a stitched sample check.
- + Shortlisting a Cosmo substitute before you buy skeins, especially if your project can tolerate small differences in sheen or dye lot.
- + Comparing this Cosmo candidate against the other conversions and nearby DMC shades linked from the page before you commit to a full swap.
Watch for
- ! Close matches are not safe to assume interchangeable in focal areas without a physical test on your fabric.
- ! Brand sheen, strand thickness, and project lighting can make DMC 791 and Cosmo 665 look further apart than the stored match rating suggests.
- ! If the design depends on smooth gradients or skin-tone transitions, compare this swap against the neighboring DMC shades before you substitute a large block.
Before you commit
- Compare DMC 791 and Cosmo 665: lay the physical skeins together in daylight before you mix brands in the same stitched area.
- Test on your project fabric: stitch a small sample so fabric color and stitch density reveal whether the match still holds at full coverage.
- Keep a fallback ready: if the swap feels off, use the linked related DMC shades or another brand conversion instead of forcing the closest stored match.
DMC 791 to Cosmo FAQ
These answers are the same statements published in this page's FAQ structured data.
What is the Cosmo equivalent of DMC 791?+
The closest Cosmo equivalent to DMC 791 (Very Dark Cornflower Blue) is Cosmo 665. This is a close match.
Is the DMC 791 to Cosmo conversion exact?+
The conversion from DMC 791 (Very Dark Cornflower Blue) to Cosmo 665 is rated as a close match. Thread colors vary slightly between brands, so compare physical thread in daylight before stitching a large area.
Can I mix DMC 791 and Cosmo 665 in the same project?+
You can use DMC 791 and Cosmo 665 together when the close match is acceptable for your project, but always test them side by side on your fabric first because sheen and dye lots can create visible differences.
Other Conversions for DMC 791
Similar DMC Colors
Shades closest to DMC 791 — handy if Cosmo 665 isn't quite right:
Free Printable Thread Conversion Chart
Pick a brand, enter your email, and we'll send you a printable chart mapping all 552 DMC colors to that brand's equivalents. Zero spam, one chart.
Thanks! Here's your free chart:
Download Your ChartOpens in a new tab. Use your browser's Print → Save as PDF.
No spam. Your email is stored securely and never shared.