DeepSeek V4 vs Laguna XS 2.1

DeepSeek · China  |  Poolside · US · Updated June 2026

Quick verdict

Pick DeepSeek V4 for near-frontier coding at ~1/12 the cost or open mit-licensed weights you can self-host. Pick Laguna XS 2.1 for remarkable efficiency — 70.9% on swe-bench verified from only 3b active parameters or open weights under openmdw-1.1, shipped day one in bf16, fp8, nvfp4 and int4 across every major runtime. On a tight budget at scale, Laguna XS 2.1 is the value pick.

DeepSeek V4 (DeepSeek, China) and Laguna XS 2.1 (Poolside, US) line up two different AI ecosystems against each other — a comparison that is as much about cost philosophy and openness as raw capability. DeepSeek V4 is china's open-weight price earthquake — near-frontier capability at roughly a twelfth of GPT-5.5's cost. Laguna XS 2.1 is a 33B open-weight coding MoE running on 3B active parameters — 70.9% SWE-Bench Verified and very cheap, but unproven. They diverge most on price, context window and coding benchmarks — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecDeepSeek V4Laguna XS 2.1
ProviderDeepSeek (China) Poolside (US)
ReleasedApril 24, 2026 July 2, 2026
Context window1M (~1,500 pages) 256K (~393 pages)
Price (in/out)$0.435/$0.87 per 1M tokens $0.1/$0.2 per 1M tokens
Open weight?Yes — self-hostable Yes — self-hostable
Modalitiestext, code text, code
SWE-Bench Verified80.6% 70.9%
MRCR v2 @ 1MNot published Not published

Who wins what

Near-frontier coding at ~1/12 the cost

DeepSeek V4

It scores 80.6% on SWE-Bench Verified against Laguna XS 2.1's 70.9% — a 9.7-point edge on real repository work.

Open MIT-licensed weights you can self-host

DeepSeek V4

China's open-weight price earthquake — near-frontier capability at roughly a twelfth of GPT-5.5's cost — and it leads SWE-Bench Verified 80.6% to 70.9%.

No long-context surcharge

DeepSeek V4

Its 1M window holds about 3.8× more than Laguna XS 2.1's 256K in a single prompt.

Remarkable efficiency — 70.9% on SWE-Bench Verified from only 3B active parameters

Laguna XS 2.1

A 33B open-weight coding MoE running on 3B active parameters — 70.9% SWE-Bench Verified and very cheap, but unproven — and it runs cheaper at $0.1/$0.2 per 1M tokens.

Open weights under OpenMDW-1.1, shipped day one in BF16, FP8, NVFP4 and INT4 across every major runtime

Laguna XS 2.1

A 33B open-weight coding MoE running on 3B active parameters — 70.9% SWE-Bench Verified and very cheap, but unproven — and it is the newer of the two.

Cheap even on the paid tier, at roughly a sixth of GLM 4.7's input price

Laguna XS 2.1

At $0.1/$0.2 per 1M tokens it undercuts DeepSeek V4 ($0.435/$0.87 per 1M tokens), and that gap compounds at volume.

Lowest cost at scale

Laguna XS 2.1

At $0.1/$0.2 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Largest single-prompt input

DeepSeek V4

Its 1M window is about 3.8× larger than Laguna XS 2.1's 256K, fitting roughly 1,500 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

Laguna XS 2.1

At $0.1/$0.2 per 1M tokens it undercuts DeepSeek V4, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

DeepSeek V4

Larger 1M window fits more in one prompt.

Anyone whose priority is near-frontier coding at ~1/12 the cost

DeepSeek V4

It is specifically built for that.

Anyone whose priority is remarkable efficiency — 70.9% on swe-bench verified from only 3b active parameters

Laguna XS 2.1

That is its strongest area.

An enterprise with regional data-residency rules

Laguna XS 2.1 or DeepSeek V4

Origin (China vs US) affects where data is processed and which compliance regime applies — check the provider's terms for your region.

DeepSeek V4: where it fits

China's open-weight price earthquake — near-frontier capability at roughly a twelfth of GPT-5.5's cost. Released April 24, 2026 by DeepSeek, it is built for near-frontier coding at ~1/12 the cost, open MIT-licensed weights you can self-host, no long-context surcharge, and highest LiveCodeBench result.

Its trade-offs are real: trails the very best on hardest agentic coding, and text/code focused, less multimodal. At $0.435 in / $0.87 out per million tokens, it sits in the budget price band.

Laguna XS 2.1: where it fits

A 33B open-weight coding MoE running on 3B active parameters — 70.9% SWE-Bench Verified and very cheap, but unproven. Released July 2, 2026 by Poolside, it is built for remarkable efficiency — 70.9% on SWE-Bench Verified from only 3B active parameters, open weights under OpenMDW-1.1, shipped day one in BF16, FP8, NVFP4 and INT4 across every major runtime, cheap even on the paid tier, at roughly a sixth of GLM 4.7's input price, and unusually transparent evaluation — it publishes its harness, step limits, and sandbox specs.

Its trade-offs: weeks old with no independent replication; every published score traces back to Poolside's own harness, the free endpoint trains on your inputs and outputs — disqualifying for proprietary code, which is its main use case, and weak on harder agentic work (37.5 on Terminal-Bench 2.0), and its gain over XS.2 is barely above noise. At $0.1 in / $0.2 out per million tokens, it sits in the budget price band.

The bottom line for this matchup

This is less "which is smarter" and more "which ecosystem fits." DeepSeek V4 (China) and Laguna XS 2.1 (US) differ on pricing philosophy, data-residency, and tooling as much as on raw scores. Laguna XS 2.1 is the cheaper option, which matters at volume. The pragmatic move is to run one real task through both and judge the outputs against your own constraints — including where your data is allowed to be processed.

Want both DeepSeek V4 and Laguna XS 2.1 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 V4 or Laguna XS 2.1 better for coding?

On SWE-Bench Verified, DeepSeek V4 scores 80.6% and Laguna XS 2.1 scores 70.9% — DeepSeek V4 has the measurable edge.

Which is cheaper, DeepSeek V4 or Laguna XS 2.1?

Laguna XS 2.1 is cheaper — $0.435/$0.87 per 1M tokens vs $0.1/$0.2 per 1M tokens, roughly 4.3× apart on input.

Which has the bigger context window?

DeepSeek V4 — 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 DeepSeek V4 and Laguna XS 2.1 together?

Yes — a multi-model platform like LumiChats gives you DeepSeek V4, Laguna XS 2.1 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 V4 or Laguna XS 2.1?

Laguna XS 2.1 — released July 2, 2026, about 2 months after DeepSeek V4.

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.