FIEmber-1 Paid vs 
Claude Sonnet 5.5 Paid
Ember-1 vs Claude Sonnet 5.5 compared — price per token, context window, multimodality, openness and which to choose. Full 2026 breakdown.
Ember-1 — full profile › · Claude Sonnet 5.5 — full profile ›
Prices & specs refreshed from live data · olud.ai
Open-model prices = cheapest provider via OpenRouter; official maker rates may be higher.
$15 /M outputManaged API (no infra to run)
$10 /M outputManaged API (no infra to run)
Ember-1 vs Claude Sonnet 5.5 specs
| Spec | Ember-1 | Claude Sonnet 5.5 | Winner |
|---|---|---|---|
| Maker | Fireworks | Anthropic | – |
| Type | Proprietary | Proprietary | – |
| Context window | 1M tokens | 1M tokens | FIEmber-1 |
| Input price | $3/M | $2/M | |
| Output price | $15/M | $10/M | |
| Vision / multimodal | Yes | Yes | = Tie |
| Tool / function calling | Yes | Yes | = Tie |
| Self-hostable | No (API only) | No (API only) | – |
| License | Proprietary | Proprietary | – |
Price gap & when to choose each
Claude Sonnet 5.5 is ~1.5× cheaper than Ember-1 on output tokens ($10 vs $15 per M tokens).
- You want frontier performance through a managed API
- You need the longer 1M context window
- You value reliability & ecosystem
- You don't want to manage infrastructure
- You want frontier performance through a managed API
- You want the lower output price
- You value reliability & ecosystem
- You don't want to manage infrastructure
Feature comparison
| Capability | Ember-1 | Claude Sonnet 5.5 |
|---|---|---|
| Open weights (downloadable) | ✗ | ✗ |
| Self-hostable | ✗ | ✗ |
| Runs fully offline | ✗ | ✗ |
| Vision / multimodal | ✓ | ✓ |
| Tool / function calling | ✓ | ✓ |
| 1M+ context window | ✓ | ✓ |
Benchmarks: Ember-1 vs Claude Sonnet 5.5
Independent benchmark scores measured by Artificial Analysis. Higher is better (except latency).
Benchmark data by Artificial Analysis.
How Ember-1 and Claude Sonnet 5.5 score
| Criterion | Ember-1 | Claude Sonnet 5.5 |
|---|---|---|
| Cost-efficiency | 3.0 | 3.5 |
| Context window | 5.0 | 5.0 |
| Openness | 1.5 | 1.5 |
| Self-hosting | 1.0 | 1.0 |
| Multimodality | 5.0 | 5.0 |
Scores come from live data — output price (cost), context length, open vs closed weights (openness & self-hosting) and vision/tool support (multimodality). Raw task quality isn't scored here; it depends on your benchmark — see the verdict.
What each model is
Ember-1 Paid
Ember-1 is a specialized reasoning model from Fireworks Research, built on [Kimi K3](https://openrouter.ai/moonshotai/kimi-k3). It is designed to make every token go further: it produces shorter reasoning traces, using roughly 40%...
Claude Sonnet 5.5 Paid
Claude Sonnet 5.5 is Anthropic's Sonnet-class model for well-scoped everyday work, succeeding Claude Sonnet 5 as a direct upgrade. It is especially strong at building features, fixing bugs, and producing...
Other models in these families
These variants are tracked but not compared here — one page per family keeps the comparison readable.
Frequently asked questions
Ember-1 vs Claude Sonnet 5.5 — which is cheaper?
Claude Sonnet 5.5 is cheaper on output ($10/M vs $15/M).
Which has the larger context window?
Ember-1 offers the larger context window (1M tokens).
Ember-1 vs Claude Sonnet 5.5 — which should I pick in 2026?
Choose Claude Sonnet 5.5 for the lower output price ($10/M vs $15/M). Choose Ember-1 if you need the larger 1M context window.
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