DeepSeek R1 vs Step 3.7 Flash

DeepSeek · China  |  StepFun · China · Updated June 2026

Quick verdict

Pick DeepSeek R1 for open-weight reasoning model or transparent chain-of-thought. 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, Step 3.7 Flash is the value pick.

DeepSeek R1 (DeepSeek) and Step 3.7 Flash (StepFun) are two of the models people most often weigh against each other in 2026. DeepSeek R1 is the open-weight reasoning model that reset price expectations in early 2025. 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

SpecDeepSeek R1Step 3.7 Flash
ProviderDeepSeek (China) StepFun (China)
ReleasedJanuary 2025 May 29, 2026
Context window128K (~192 pages) 256K (~393 pages)
Price (in/out)$0.55/$2.19 per 1M tokens $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

Open-weight reasoning model

DeepSeek R1

DeepSeek R1 lists open-weight reasoning model among its strengths; Step 3.7 Flash does not.

Transparent chain-of-thought

DeepSeek R1

DeepSeek R1 lists transparent chain-of-thought among its strengths; Step 3.7 Flash does not.

Low cost

DeepSeek R1

DeepSeek R1 lists low cost among its strengths; Step 3.7 Flash does not.

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

Step 3.7 Flash

DeepSeek R1 is comparatively weak here — discontinued - no longer offered as a standalone model via DeepSeek's API as of mid-2026; the legacy alias that used to point to it stopped working July 24, 2026

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

Step 3.7 Flash

StepFun's 198B MoE vision-language model built for coding and search agents - a distinct Chinese lab with genuinely competitive open weights — and it runs cheaper at $0.2/$1.15 per 1M tokens.

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

Step 3.7 Flash

At $0.2/$1.15 per 1M tokens it undercuts DeepSeek R1 ($0.55/$2.19 per 1M tokens), and that gap compounds at volume.

Lowest cost at scale

Step 3.7 Flash

At $0.2/$1.15 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Largest single-prompt input

Step 3.7 Flash

Its 256K window is about 2× larger than DeepSeek R1's 128K, fitting roughly 393 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

Step 3.7 Flash

At $0.2/$1.15 per 1M tokens it undercuts DeepSeek R1, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

Step 3.7 Flash

Larger 256K window fits more in one prompt.

Anyone whose priority is open-weight reasoning model

DeepSeek R1

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.

DeepSeek R1: where it fits

The open-weight reasoning model that reset price expectations in early 2025. Released January 2025 by DeepSeek, it is built for open-weight reasoning model, transparent chain-of-thought, low cost, and strong maths and code.

Its trade-offs are real: discontinued - no longer offered as a standalone model via DeepSeek's API as of mid-2026; the legacy alias that used to point to it stopped working July 24, 2026, older than V4, smaller 128K context, and text/code focused. At $0.55 in / $2.19 out per million tokens, it sits in the budget price band.

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

DeepSeek R1 and Step 3.7 Flash overlap enough that the right pick depends on your specific job. Step 3.7 Flash costs less per token; Step 3.7 Flash holds the larger context; and each leads in its own area — DeepSeek R1 for open-weight reasoning model, 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 DeepSeek R1 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 DeepSeek R1 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, DeepSeek R1 leans toward open-weight reasoning model 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, DeepSeek R1 or Step 3.7 Flash?

Step 3.7 Flash is cheaper — $0.55/$2.19 per 1M tokens vs $0.2/$1.15 per 1M tokens, roughly 2.8× apart on input.

Which has the bigger context window?

Step 3.7 Flash — 256K vs 128K, about 2× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both DeepSeek R1 and Step 3.7 Flash together?

Yes — a multi-model platform like LumiChats gives you DeepSeek R1, 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, DeepSeek R1 or Step 3.7 Flash?

Step 3.7 Flash — released May 29, 2026, about 16 months after DeepSeek R1.

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.