o4 vs Yi-Lightning
A complete head-to-head: pricing, context window, benchmarks, modality coverage, and openness, with a programmatic verdict synthesized from the underlying data.
Updated
o4 specs · Yi-Lightning specs- PriceYi-Lightning
Yi-Lightning publishes pricing ($0.14 / 1M output tokens) while o4 does not.
- Context windowo4
o4 accepts 200K tokens vs 16K, 12.5× the room for long documents and codebases.
- BenchmarksTie
No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores.
- Modalitieso4
o4 supports 2 modalities (text, vision) vs 1 for Yi-Lightning.
- OpennessTie
Both are closed-weight, API-only.
On balance o4 edges ahead, winning 2 of 5 categories against Yi-Lightning's 1. Yi-Lightning publishes pricing ($0.14 / 1M output tokens) while o4 does not. o4 accepts 200K tokens vs 16K, 12.5× the room for long documents and codebases.
No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores. They differ in modality coverage, o4 handles text, vision while Yi-Lightning handles text, which can be the deciding factor before you even look at benchmarks. Both are closed-weight, API-only.
o4 is the newer of the two, released 14 months after Yi-Lightning, which usually means a more recent knowledge cutoff and updated safety post-training. o4 is usually picked for reasoning and math workloads, while Yi-Lightning sees more deployments in chinese llm and cheapest llm. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.
Side-by-side specs
| Spec | o4 | Yi-Lightning |
|---|---|---|
| Provider | OpenAI | Other |
| Released | Dec 2025 | Oct 2024 |
| Modalities | text, vision | text |
| Context window | 200K tokens | 16K tokens |
| Max output | , | , |
| Input · 1M | Pricing not published | $0.14 / 1M tokens |
| Output · 1M | Pricing not published | $0.14 / 1M tokens |
| Knowledge cutoff | , | , |
| Open weights | No | No |
| API available | Yes | Yes |
Pricing at scale
What you'd actually pay at typical workloads. Numbers come from each model's published per-million-token rates.
- Light usage, 100k in / 50k out per day, vs $0.630
- Heavy usage, 1M in / 500k out per day, vs $6.30
- RAG workload, 5M in / 200k out per day, vs $21.84
Light usage, 100k in / 50k out per day: pricing not directly comparable (one or both models are missing public per-token rates). Heavy usage, 1M in / 500k out per day: pricing not directly comparable (one or both models are missing public per-token rates). RAG workload, 5M in / 200k out per day: pricing not directly comparable (one or both models are missing public per-token rates).
Estimated spend for the listed models at your usage. Numbers are derived from each model's published per-million-token rates.
- o4Pricing unavailable
- Yi-Lightning$0.021
Benchmarks compared
Only sourced numbers. Where a benchmark is missing for one model we show the available value rather than fabricating the other.
o4 fits when…
- Exceptional performance on hard math and reasoning benchmarks
- Good at multi-step planning and verification
- Strong scientific reasoning
- Long-context tasks, handles 200K tokens vs 16K for Yi-Lightning.
- Multimodal needs covering vision.
Yi-Lightning fits when…
- Cheap
- Strong Chinese
- Fast
Consider GPT-5.5
OpenAI's mid-cycle GPT-5 refresh, improved reasoning, tool use, and multimodal grounding over the 2025 launch.
Frequently asked
Is o4 or Yi-Lightning cheaper?
Per-token pricing isn't published for at least one of these models, check each model's spec page for current rates.Which has the larger context window?
o4 accepts 200K tokens vs 16K for Yi-Lightning.Is o4 or Yi-Lightning better for coding?
Both o4 and Yi-Lightning are competitive on coding benchmarks. See each model's individual spec page for HumanEval and SWE-bench scores where published. For an opinionated pick, consult our Best LLM for Coding ranking.Are either of these models open source?
Neither model ships open weights, both are accessible only via their respective providers' APIs.When were o4 and Yi-Lightning released?
o4 was released by OpenAI on 2025-12-15. Yi-Lightning was released by Other on 2024-10-16.
The week's AI launches, in your inbox.
One short email every Friday, new models, leaks, and quietly-shipped APIs you missed.