Spark X2.5 Models by iFLYTEK Developer
2 models2026Up to 1.05m ctx
Last refreshed 2026-09-01. Next refresh: weekly.
Details
ResearcheriFLYTEK Developer
LicenseApache 2.0OSI-approved
Commercial useCommercial use: permitted
Models2
Released2026
Max context1.05m
Capabilities
ReasoningAll models
JSON / Tool useAll models
About
Spark-X2.5 is SparkLLM / XHToken (iFlytek) on-device general LLM family with hybrid full + sliding-window attention and native 1M-token context. Open-weight SKUs Spark-X2.5-4B and Spark-X2.5-1.7B. Compare it for Agents, Coding, and Long context.
Decision facts
- Best fit
- agenticagentcoding
- Capability starting point
- Spark X2.5 4B with 1.05m context and reasoning and JSON / Tool use
- Lowest tracked input
- Not tracked
- Closest related family
- Claude 3
Current Variants
Use-when guidance is based on each model's tracked capabilities, context window, release date, and replacement status.
2 in view
Spark X2.5 4BCurrent
Use when the workload needs agentic, 1.05m context, and 4B parameters.
2026-08agentic1.05m context4B parameters
Spark X2.5 1.7BCurrent
Use when the workload needs agentic, 1.05m context, and 1.7B parameters.
2026-08agentic1.05m context1.7B parameters
| Model | Use when | Released | Signals | Status |
|---|---|---|---|---|
| Spark X2.5 4B | Use when the workload needs agentic, 1.05m context, and 4B parameters. | 2026-08 | agentic1.05m context4B parameters | Current |
| Spark X2.5 1.7B | Use when the workload needs agentic, 1.05m context, and 1.7B parameters. | 2026-08 | agentic1.05m context1.7B parameters | Current |
Release Timeline
1 release group2026-08
2 current
Spark X2.5 1.7B
Currentagentic1.05m context1.7B parameters
Spark X2.5 4B
Currentagentic1.05m context4B parameters
Specifications(2 models)
| Model | Released | Context | Parameters | Reasoning | JSON / Tool use |
|---|---|---|---|---|---|
| Spark X2.5 4B | 2026-08 | 1.05m | 4B | Yes | Yes |
| Spark X2.5 1.7B | 2026-08 | 1.05m | 1.7B | Yes | Yes |