Laguna XS 2.1 vs Microsoft Phi-4

Poolside · US  |  Microsoft · US · Updated June 2026

Quick verdict

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. Pick Microsoft Phi-4 for strong reasoning for a small 14b open-weight model or mit-licensed — fully self-hostable at no per-token cost. On a tight budget at scale, Microsoft Phi-4 is the value pick.

Laguna XS 2.1 (Poolside) and Microsoft Phi-4 (Microsoft) are two of the models people most often weigh against each other in 2026. 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. Microsoft Phi-4 is microsoft's MIT-licensed 14B open model — strong reasoning for its size and very cheap, but a tiny 16K context and text-only. 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

SpecLaguna XS 2.1Microsoft Phi-4
ProviderPoolside (US) Microsoft (US)
ReleasedJuly 2, 2026 January 10, 2025
Context window256K (~393 pages) 16K (~25 pages)
Price (in/out)$0.1/$0.2 per 1M tokens $0.07/$0.14 per 1M tokens
Open weight?Yes — self-hostable Yes — self-hostable
Modalitiestext, code text, code
SWE-Bench Verified70.9% Not published
MRCR v2 @ 1MNot published Not published

Who wins what

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 carries the larger 256K context.

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

Microsoft Phi-4 is comparatively weak here — text only — no image, audio or video input

Strong reasoning for a small 14B open-weight model

Microsoft Phi-4

Microsoft's MIT-licensed 14B open model — strong reasoning for its size and very cheap, but a tiny 16K context and text-only — and it runs cheaper at $0.07/$0.14 per 1M tokens.

MIT-licensed — fully self-hostable at no per-token cost

Microsoft Phi-4

At $0.07/$0.14 per 1M tokens it undercuts Laguna XS 2.1 ($0.1/$0.2 per 1M tokens), and that gap compounds at volume.

Runs on modest or local hardware

Microsoft Phi-4

Microsoft Phi-4 lists runs on modest or local hardware among its strengths; Laguna XS 2.1 does not.

Lowest cost at scale

Microsoft Phi-4

At $0.07/$0.14 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Largest single-prompt input

Laguna XS 2.1

Its 256K window is about 16× larger than Microsoft Phi-4's 16K, fitting roughly 393 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

Microsoft Phi-4

At $0.07/$0.14 per 1M tokens it undercuts Laguna XS 2.1, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

Laguna XS 2.1

Larger 256K window fits more in one prompt.

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

Laguna XS 2.1

It is specifically built for that.

Anyone whose priority is strong reasoning for a small 14b open-weight model

Microsoft Phi-4

That is its strongest area.

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 are real: 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.

Microsoft Phi-4: where it fits

Microsoft's MIT-licensed 14B open model — strong reasoning for its size and very cheap, but a tiny 16K context and text-only. Released January 10, 2025 by Microsoft, it is built for strong reasoning for a small 14B open-weight model, mIT-licensed — fully self-hostable at no per-token cost, runs on modest or local hardware, and very cheap hosted inference at about $0.07/$0.14.

Its trade-offs: a tiny 16K context — by far the smallest window in this comparison, text only — no image, audio or video input, an early-2025 small model, outclassed on hard tasks by 2026 flagships, and no first-party per-token API; hosted prices are third-party. At $0.07 in / $0.14 out per million tokens, it sits in the budget price band.

The bottom line for this matchup

Laguna XS 2.1 and Microsoft Phi-4 overlap enough that the right pick depends on your specific job. Microsoft Phi-4 costs less per token; Laguna XS 2.1 holds the larger context; and each leads in its own area — Laguna XS 2.1 for remarkable efficiency — 70.9% on swe-bench verified from only 3b active parameters, Microsoft Phi-4 for strong reasoning for a small 14b open-weight model. Rather than crowning one, run the same hard task through both once and let the results decide.

Want both Laguna XS 2.1 and Microsoft Phi-4 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 Laguna XS 2.1 or Microsoft Phi-4 better for coding?

Public SWE-Bench figures are not available for Microsoft Phi-4, so the honest test is your own repository — run an identical real bug through both. By design, Laguna XS 2.1 leans toward remarkable efficiency — 70.9% on swe-bench verified from only 3b active parameters while Microsoft Phi-4 leans toward strong reasoning for a small 14b open-weight model, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Laguna XS 2.1 or Microsoft Phi-4?

Microsoft Phi-4 is cheaper — $0.1/$0.2 per 1M tokens vs $0.07/$0.14 per 1M tokens, roughly 1.4× apart on input.

Which has the bigger context window?

Laguna XS 2.1 — 256K vs 16K, about 16× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both Laguna XS 2.1 and Microsoft Phi-4 together?

Yes — a multi-model platform like LumiChats gives you Laguna XS 2.1, Microsoft Phi-4 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, Laguna XS 2.1 or Microsoft Phi-4?

Laguna XS 2.1 — released July 2, 2026, about 18 months after Microsoft Phi-4.

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.