LongCat-2.0 vs Step 3.7 Flash

Meituan · China  |  StepFun · China · Updated June 2026

Quick verdict

Pick LongCat-2.0 for near-frontier agentic coding — topped openrouter anonymously as 'owl alpha' for two months or massive native 1m context at near-linear cost via sparse attention. Pick Step 3.7 Flash for a 198b-parameter sparse moe vision-language model (11b active) built specifically for agentic coding and search workflows or scmp reported it 'outshines larger rivals' from deepseek and moonshot on some benchmarks despite its smaller active size. On a tight budget at scale, LongCat-2.0 is the value pick.

LongCat-2.0 (Meituan) and Step 3.7 Flash (StepFun) are two of the models people most often weigh against each other in 2026. LongCat-2.0 is a trillion-parameter, MIT-licensed open MoE delivering near-frontier agentic coding at 1M context — trained entirely on Chinese chips. Step 3.7 Flash is stepFun's 198B MoE vision-language model built for coding and search agents - a distinct Chinese lab with genuinely competitive open weights. They diverge most on price and context window — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecLongCat-2.0Step 3.7 Flash
ProviderMeituan (China) StepFun (China)
ReleasedJuly 5, 2026 May 29, 2026
Context window1M (~1,500 pages) 256K (~393 pages)
Price (in/out)Open weight (self-host / free) $0.2/$1.15 per 1M tokens
Open weight?Yes — self-hostable Yes — self-hostable
Modalitiestext, code text, image, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Near-frontier agentic coding — topped OpenRouter anonymously as 'Owl Alpha' for two months

LongCat-2.0

A trillion-parameter, MIT-licensed open MoE delivering near-frontier agentic coding at 1M context — trained entirely on Chinese chips — and it carries the larger 1M context.

Massive native 1M context at near-linear cost via sparse attention

LongCat-2.0

Its 1M window holds about 3.8× more than Step 3.7 Flash's 256K in a single prompt.

Fully MIT-licensed 1.6T-parameter mixture-of-experts (about 48B active)

LongCat-2.0

A trillion-parameter, MIT-licensed open MoE delivering near-frontier agentic coding at 1M context — trained entirely on Chinese chips — and it is the newer of the two.

A 198B-parameter sparse MoE vision-language model (11B active) built specifically for agentic coding and search workflows

Step 3.7 Flash

LongCat-2.0 is comparatively weak here — a 1.6T model is extremely expensive to self-host, so most use leans on the China-hosted API

SCMP reported it 'outshines larger rivals' from DeepSeek and Moonshot on some benchmarks despite its smaller active size

Step 3.7 Flash

LongCat-2.0 is comparatively weak here — headline scores are vendor-reported on SWE-Bench Pro, not the Verified set

Open weights (Apache 2.0) at a low per-token price

Step 3.7 Flash

Step 3.7 Flash lists open weights (Apache 2.0) at a low per-token price among its strengths; LongCat-2.0 does not.

Lowest cost at scale

LongCat-2.0

Its weights are open, so at volume you pay for your own hardware instead of Step 3.7 Flash's $0.2/$1.15 per 1M tokens.

Largest single-prompt input

LongCat-2.0

Its 1M window is about 3.8× larger than Step 3.7 Flash's 256K, fitting roughly 1,500 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

LongCat-2.0

At Open weight (self-host / free) it undercuts Step 3.7 Flash, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

LongCat-2.0

Larger 1M window fits more in one prompt.

Anyone whose priority is near-frontier agentic coding — topped openrouter anonymously as 'owl alpha' for two months

LongCat-2.0

It is specifically built for that.

Anyone whose priority is a 198b-parameter sparse moe vision-language model (11b active) built specifically for agentic coding and search workflows

Step 3.7 Flash

That is its strongest area.

LongCat-2.0: where it fits

A trillion-parameter, MIT-licensed open MoE delivering near-frontier agentic coding at 1M context — trained entirely on Chinese chips. Released July 5, 2026 by Meituan, it is built for near-frontier agentic coding — topped OpenRouter anonymously as 'Owl Alpha' for two months, massive native 1M context at near-linear cost via sparse attention, fully MIT-licensed 1.6T-parameter mixture-of-experts (about 48B active), and trained end to end on domestic Chinese chips, independent of Nvidia hardware.

Its trade-offs are real: a 1.6T model is extremely expensive to self-host, so most use leans on the China-hosted API, and headline scores are vendor-reported on SWE-Bench Pro, not the Verified set. As an open-weight model, its running cost is your own hardware rather than a per-token fee.

Step 3.7 Flash: where it fits

StepFun's 198B MoE vision-language model built for coding and search agents - a distinct Chinese lab with genuinely competitive open weights. Released May 29, 2026 by StepFun, it is built for a 198B-parameter sparse MoE vision-language model (11B active) built specifically for agentic coding and search workflows, sCMP reported it 'outshines larger rivals' from DeepSeek and Moonshot on some benchmarks despite its smaller active size, open weights (Apache 2.0) at a low per-token price, and includes a 1.8B vision encoder for image understanding alongside text.

Its trade-offs: stepFun is a newer, less established lab than DeepSeek, Alibaba, or Moonshot, benchmark 'outshines rivals' claims are from press coverage of specific tests, not a full independent leaderboard sweep, and smaller ecosystem and less third-party documentation than the more established Chinese labs. At $0.2 in / $1.15 out per million tokens, it sits in the budget price band.

The bottom line for this matchup

LongCat-2.0 and Step 3.7 Flash overlap enough that the right pick depends on your specific job. LongCat-2.0 costs less per token; LongCat-2.0 holds the larger context; and each leads in its own area — LongCat-2.0 for near-frontier agentic coding — topped openrouter anonymously as 'owl alpha' for two months, Step 3.7 Flash for a 198b-parameter sparse moe vision-language model (11b active) built specifically for agentic coding and search workflows. Rather than crowning one, run the same hard task through both once and let the results decide.

Want both LongCat-2.0 and Step 3.7 Flash without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.

See pricing

Frequently asked questions

Is LongCat-2.0 or Step 3.7 Flash better for coding?

Public SWE-Bench figures are not available for either model, so the honest test is your own repository — run an identical real bug through both. By design, LongCat-2.0 leans toward near-frontier agentic coding — topped openrouter anonymously as 'owl alpha' for two months while Step 3.7 Flash leans toward a 198b-parameter sparse moe vision-language model (11b active) built specifically for agentic coding and search workflows, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, LongCat-2.0 or Step 3.7 Flash?

LongCat-2.0 is cheaper — Open weight (self-host / free) vs $0.2/$1.15 per 1M tokens.

Which has the bigger context window?

LongCat-2.0 — 1M vs 256K, about 3.8× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both LongCat-2.0 and Step 3.7 Flash together?

Yes — a multi-model platform like LumiChats gives you LongCat-2.0, Step 3.7 Flash and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.

Which is newer, LongCat-2.0 or Step 3.7 Flash?

LongCat-2.0 — released July 5, 2026, about 37 days after Step 3.7 Flash.

Related comparisons

Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.