If you’re a CS2 or CS:GO collector, chances are you’ve heard about Doppler knives—famed for their vibrant colors and rare patterns. This guide will help you understand all Doppler phases, from Phase 1 to Phase 4, including the coveted Sapphire and Ruby variants. We’ll also cover pattern templates, best phases, and how to spot rare Doppler knives in-game.
What Are Doppler Knives in CS2?
A Doppler knife is a type of rare skin in CS2 and CS:GO known for its shimmering, color-shifting finish. Doppler knives are categorized into phases (Phase 1–4), with each phase showing a different dominant color pattern. Some Dopplers like Sapphire or Ruby are even rarer and highly sought after.
Standard Phases
- Phase 1 Doppler: Deep purple and subtle blue, elegant and understated.

- Phase 2 Doppler: Bright pink and purple, highly popular for collectors.

- Phase 3 Doppler: Dark blues with hints of green and black.

- Phase 4 Doppler: Bright blue, visually striking in-game.

Rare Variants
- Ruby Doppler: Solid red, extremely rare.
- Sapphire Doppler Karambit: Iconic deep blue, collector favorite.
- Black Pearl: Dark purple with subtle iridescence, the rarest variant.
These phases exist across Karambit, Bayonet, M9, Flip, and Butterfly knives, but Karambits are the most iconic due to their animation and blade shape.
Doppler Knife Phases And Float Ranges
| Phase | Color Pattern | Popular Knife Models | Rarity | Float Range | Collector Notes |
| Phase 1 | Purple & Blue | Karambit, Bayonet | Common | 0.00–0.07 | Elegant, classic look |
| Phase 2 | Pink & Purple | Karambit, M9 | Common | 0.00–0.07 | Highly aesthetic |
| Phase 3 | Deep Blue & Green | Karambit, Flip | Common | 0.00–0.07 | Unique, subtle |
| Phase 4 | Bright Blue | Karambit, Bayonet | Common | 0.00–0.07 | Eye-catching, mid-value |
| Ruby | Solid Red | Karambit, Butterfly | Rare | 0.00–0.07 | Investment-grade |
| Sapphire | Solid Blue | Karambit, M9 | Rare | 0.00–0.07 | Iconic, high demand |
| Black Pearl | Dark Purple | Karambit, Bayonet | Ultra Rare | 0.00–0.07 | Collector’s gem |
Tip: The Doppler pattern index and float significantly impact how colors appear, even within the same phase.
All Doppler Phases Explained
Doppler knives come in multiple phases. Each phase has distinct colors, and knowing them helps collectors and traders identify rare knives.
| Phase | Dominant Colors | Notes |
| Phase 1 Doppler | Mostly purple with streaks of black | Most common phase |
| Phase 2 Doppler | Purple with subtle hints of blue | Slightly rarer, smooth color transition |
| Phase 3 Doppler | Balanced mix of purple and black | Popular among collectors |
| Phase 4 Doppler | Mostly black with purple highlights | Rarest among normal Dopplers |
| Sapphire Doppler Karambit | Solid blue | Ultra-rare and highly valued |
| Ruby Doppler | Solid red | Rare and expensive collector’s item |
| Black Pearl Doppler | Black with subtle rainbow shine | Very rare, top-tier collectible |
Pro Tip: The best Doppler phase for trading often depends on color preference and rarity. Sapphire and Ruby phases usually fetch the highest market value.
Doppler Knife Patterns & Templates
Each Doppler knife has a pattern index, which slightly changes the look of the knife even within the same phase. Players use CSGO Doppler pattern templates to predict and inspect these patterns.
- Pattern Index: A number that defines the exact color arrangement on the knife.
- Doppler Pattern Sheet: Lists rare patterns for each knife type.
Knowing the pattern index can help you find unique variants like Phase 1 Karambit Doppler with a full purple blade or Phase 2 Bayonet Doppler.
How to Identify Doppler Knives in CS2
- Inspect in-game – Open your inventory and inspect the knife closely.
- Check the phase – Look for dominant colors to determine Phase 1–4.
- Pattern index – Use a Doppler pattern sheet or template to check for rare patterns.
- Float value – A lower float can make colors pop more.
You can learn more about checking your float in CS2 from our guide of Float Value Explanation.
Most Popular Doppler Knives
Some Doppler knives have become iconic in the CS2 community:
- Karambit Doppler Phases – Popular for animations and curved blade design.
- Sapphire Karambit – Solid blue, a collector’s favorite.
- Bayonet Doppler Phases – Straight blade, colorful patterns.
- CSGO Purple Knife – Mostly from Phase 1 or Phase 2 Dopplers.
- Blue Doppler – Rare, often Sapphire or Phase 2–4 mix.
For collectors, understanding which cases have Doppler knives can help in trading and opening cases. Check our How To Get Cases In CS2 guide for more help about getting cases or buying them.
Rare Doppler Variants
Some Doppler knives are considered ultra-rare due to their color intensity or pattern perfection:
- Sapphire Doppler Karambit / CS2 Sapphire Karambit – Solid blue blade

- Ruby Doppler – Solid red

- Black Pearl – Black with rainbow sheen

Collectors often search for colorphase shooting gloves to match Doppler knives for a complete aesthetic.
Tips for Collecting & Trading Doppler Knives
- Always inspect the pattern index before buying or trading.
- Phase 1 and 2 Dopplers are common but can still look stunning.
- Phase 3 and 4 Dopplers are rarer, often pricier.
- Use reputable market platforms for CS2 trading.
- Keep an eye on upcoming cases for new Doppler knife drops.
Read our full guide on most expensive CS2 knives for trading tips.
Doppler Knife Quick Reference
- All Doppler Knives: Karambit, Bayonet, Butterfly
- All Doppler Phases: Phase 1 → Phase 4, Sapphire, Ruby, Black Pearl
- Best Doppler Phase: Sapphire or Ruby (rare), Phase 3 or 4 (common)
- Pattern Index: Helps spot rare color variations
FAQs About Doppler Phases
Q: What cases have Doppler knives?
A: Doppler knives appear in rare CS2 cases. Check our CS2 case guide for details.
Q: Which Doppler knife is the rarest?
A: Sapphire Karambit, Ruby Doppler, and Black Pearl are top-tier rare.
Q: How can I identify Doppler knife phases?
A: Check the blade’s dominant colors and pattern index. Phase 1–4 and Sapphire/Ruby variants are easily distinguishable.
Conclusion
Understanding CS2 Doppler phases is essential for collectors, traders, and enthusiasts. From Phase 1 Karambit Doppler to ultra-rare Sapphire Karambits, knowing the patterns and phases will help you make smarter trades and build a stunning inventory.