StepFun Step 3.5 Flash
Free tier available
- Self-hosted (Apache 2.0)$0
- API (StepFun / OpenRouter)Usage-based/per 1M tokens

StepFun Step 3.5 Flash
Our pickGitHub Copilot
GPT-5.4 (Pro) / Claude Opus 4.7 + GPT-5.4 (Pro+)
Tier-list head-to-head. GitHub Copilot takes the A-tier slot — here's the breakdown.
Spec sheet
| Tier | B-tier | A-tierwin |
| Overall score | 7.8 / 10 | 8.3 / 10win |
| Powered by | — | GPT-5.4 (Pro) / Claude Opus 4.7 + GPT-5.4 (Pro+) |
| Free tier | Yes | Yes |
| Starting price | $0 | $0 |
| Best for | Teams building agent systems on Chinese open-weight foundations who want something other than DeepSeek or Q… | Existing Copilot subscribers on Business/Enterprise or grandfathered Pro/Pro+ seats. |
| Last reviewed | 2026-04-17 | 2026-05-21 |
Head-to-head
Rated 1-10 on the same rubric across all 130 tools we cover.
What you'll pay
Look past the headline number -- entry-tier limits drive most cost surprises.
Free tier available
Free tier available
The decision
Use-case anchors and category strengths, side by side.
Teams building agent systems on Chinese open-weight foundations who want something other than DeepSeek or Qwen, especially if agentic tool-use is the primary workload. Also good for Chinese-market products where StepFun's domestic tuning advantages matter. And for anyone looking to add diversity to their open-weight evaluation matrix beyond the top-3 Chinese labs.
Visit StepFun Step 3.5 FlashExisting Copilot subscribers on Business/Enterprise or grandfathered Pro/Pro+ seats. Also new Free-tier users -- the entry point is still open and inline completions are still best-in-class.
Visit GitHub CopilotBottom line
GitHub Copilot edges out StepFun Step 3.5 Flash by 0.5 points (8.3 vs 7.8) -- a A-tier vs B-tier split that's narrow but real. Not a blowout; both belong on a shortlist. The score gap shows up most clearly in the categories that matter for GitHub Copilot's strengths, so if those categories are your priority, the lead translates.
Pricing-wise, both tools have a free tier (StepFun Step 3.5 Flash starts $0, GitHub Copilot starts $0), so you can test either without committing. Compare what each free tier actually unlocks -- usage caps, model access, and feature gates differ a lot more than the headline price suggests, especially as both vendors have tightened limits in 2026.
By use case: pick StepFun Step 3.5 Flash when teams building agent systems on chinese open-weight foundations who want something other than deepseek or qwen, especially if agentic tool-use is the primary workload. Pick GitHub Copilot when existing copilot subscribers on business/enterprise or grandfathered pro/pro+ seats. The two tools aren't fighting for the same person -- they're aiming at adjacent jobs that occasionally overlap. If you're squarely in GitHub Copilot's lane, the tier-list ranking and the use-case fit point the same direction; if you're in StepFun Step 3.5 Flash's lane, the score gap matters less than the fit.
Bottom line: GitHub Copilot is the safer default for most readers, but StepFun Step 3.5 Flash is competitive enough that the tie-breaker is your specific workload, not the spec sheet.
Keep digging
Full StepFun Step 3.5 Flash review
Tier B · 7.8/10
Full GitHub Copilot review
Tier A · 8.3/10
StepFun Step 3.5 Flash alternatives
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GitHub Copilot alternatives
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Built from our daily AI-tool sweep, last touched May 21, 2026. Honest tier-list reviews — no affiliate-link pieces disguised as advice. See the rubric or how we review.