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Claude Sonnet 4 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

Claude Sonnet 4 specs · Yi-Lightning specs
Verdict by category
  • PriceYi-Lightning

    Yi-Lightning is roughly 107.1× cheaper on output tokens ($0.14 vs $15.00 per 1M).

  • Context windowClaude Sonnet 4

    Claude Sonnet 4 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.

  • ModalitiesClaude Sonnet 4

    Claude Sonnet 4 supports 2 modalities (text, vision) vs 1 for Yi-Lightning.

  • OpennessTie

    Both are closed-weight, API-only.

On balance Claude Sonnet 4 edges ahead, winning 2 of 5 categories against Yi-Lightning's 1. Yi-Lightning is roughly 107.1× cheaper on output tokens ($0.14 vs $15.00 per 1M). Claude Sonnet 4 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, Claude Sonnet 4 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.

Claude Sonnet 4 is the newer of the two, released 7 months after Yi-Lightning, which usually means a more recent knowledge cutoff and updated safety post-training. Claude Sonnet 4 is usually picked for coding llm and rag 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

SpecClaude Sonnet 4Yi-Lightning
ProviderAnthropicOther
ReleasedMay 2025Oct 2024
Modalitiestext, visiontext
Context window200K tokens16K tokens
Max output,,
Input · 1M$3.00 / 1M tokens$0.14 / 1M tokens
Output · 1M$15.00 / 1M tokens$0.14 / 1M tokens
Knowledge cutoff2025-03,
Open weightsNoNo
API availableYesYes

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$31.50 vs $0.630
  • Heavy usage, 1M in / 500k out per day$315 vs $6.30
  • RAG workload, 5M in / 200k out per day$540 vs $21.84

Light usage, 100k in / 50k out per day: $31.50 vs $0.630 per month, model B comes out ahead. Heavy usage, 1M in / 500k out per day: $315 vs $6.30 per month, model B comes out ahead. RAG workload, 5M in / 200k out per day: $540 vs $21.84 per month, model B comes out ahead.

Price calculator

Estimated spend for the listed models at your usage. Numbers are derived from each model's published per-million-token rates.

  • Claude Sonnet 4$1.05
  • 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.

Claude Sonnet 4Yi-Lightning
  • SWE-bench Verified65.0
Pick Claude Sonnet 4 if

Claude Sonnet 4 fits when…

  • Solid all-rounder
  • Mature deployment ecosystem
  • Long-context tasks, handles 200K tokens vs 16K for Yi-Lightning.
  • Multimodal needs covering vision.
Pick Yi-Lightning if

Yi-Lightning fits when…

  • Cheap
  • Strong Chinese
  • Fast
  • Cost-sensitive workloads, 107.1× cheaper than Claude Sonnet 4 on output tokens.
Don't want either?

Consider Claude Opus 4.7

Anthropic's mid-2026 flagship, ahead on SWE-bench, agent reliability, and writing quality.

See Claude Opus 4.7 specsClaude Sonnet 4 vs Claude Opus 4.7Yi-Lightning vs Claude Opus 4.7

Frequently asked

  • Is Claude Sonnet 4 or Yi-Lightning cheaper?
    Yi-Lightning is cheaper at $0.14 / 1M tokens per million output tokens, vs $15.00 / 1M tokens for Claude Sonnet 4.
  • Which has the larger context window?
    Claude Sonnet 4 accepts 200K tokens vs 16K for Yi-Lightning.
  • Is Claude Sonnet 4 or Yi-Lightning better for coding?
    Both Claude Sonnet 4 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 Claude Sonnet 4 and Yi-Lightning released?
    Claude Sonnet 4 was released by Anthropic on 2025-05-22. Yi-Lightning was released by Other on 2024-10-16.
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