GPT-5.4 Nano vs LongCat-2.5

OpenAI · US  |  Meituan · China · Updated June 2026

Quick verdict

Pick GPT-5.4 Nano for cheapest gpt-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work or classification, extraction, ranking and sub-agent execution at scale. Pick LongCat-2.5 for native multimodal upgrade to longcat-2.0 - 1.6t total parameters, about 48b active per token or limited-time api price of $0.30/$1.20 per million tokens (cached input $0.006). On a tight budget at scale, GPT-5.4 Nano is the value pick.

GPT-5.4 Nano (OpenAI, US) and LongCat-2.5 (Meituan, China) line up two different AI ecosystems against each other — a comparison that is as much about cost philosophy and openness as raw capability. GPT-5.4 Nano is openAI's cheapest GPT-5.4 variant at $0.20/$1.25 with a 400K window — a speed-and-cost tier for high-volume tasks, not deep reasoning. LongCat-2.5 is meituan's November 2, 2026 natively multimodal successor to LongCat-2.0 - 1.6T parameters and 1M context at $0.30/$1.20, with open weights planned but undated. 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

SpecGPT-5.4 NanoLongCat-2.5
ProviderOpenAI (US) Meituan (China)
ReleasedMarch 17, 2026 November 2, 2026
Context window400K (~600 pages) 1M tokens (~1,500 pages)
Price (in/out)$0.2/$1.25 per 1M tokens $0.3/$1.2 per 1M tokens
Open weight?No — API only No — API only
Modalitiestext, image, code text, image, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Cheapest GPT-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work

GPT-5.4 Nano

At $0.2/$1.25 per 1M tokens it undercuts LongCat-2.5 ($0.3/$1.2 per 1M tokens), and that gap compounds at volume.

Classification, extraction, ranking and sub-agent execution at scale

GPT-5.4 Nano

OpenAI's cheapest GPT-5.4 variant at $0.20/$1.25 with a 400K window — a speed-and-cost tier for high-volume tasks, not deep reasoning — and it runs cheaper at $0.2/$1.25 per 1M tokens.

A 400K context in the smallest, fastest GPT-5.4 variant

GPT-5.4 Nano

GPT-5.4 Nano lists a 400K context in the smallest, fastest GPT-5.4 variant among its strengths; LongCat-2.5 does not.

Native multimodal upgrade to LongCat-2.0 - 1.6T total parameters, about 48B active per token

LongCat-2.5

Its 1M tokens window holds about 2.5× more than GPT-5.4 Nano's 400K in a single prompt.

Limited-time API price of $0.30/$1.20 per million tokens (cached input $0.006)

LongCat-2.5

GPT-5.4 Nano is comparatively weak here — image input only — no audio or video

Meituan-reported Terminal-Bench v2.1 of 88.4, up from 70.8 for LongCat-2.0

LongCat-2.5

GPT-5.4 Nano is comparatively weak here — no published SWE-Bench Verified score (OpenAI reported SWE-Bench Pro instead)

Lowest cost at scale

GPT-5.4 Nano

At $0.2/$1.25 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Largest single-prompt input

LongCat-2.5

Its 1M tokens window is about 2.5× larger than GPT-5.4 Nano's 400K, fitting roughly 1,500 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

→ GPT-5.4 Nano

At $0.2/$1.25 per 1M tokens it undercuts LongCat-2.5, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

→ LongCat-2.5

Larger 1M tokens window fits more in one prompt.

Anyone whose priority is cheapest gpt-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work

→ GPT-5.4 Nano

It is specifically built for that.

Anyone whose priority is native multimodal upgrade to longcat-2.0 - 1.6t total parameters, about 48b active per token

→ LongCat-2.5

That is its strongest area.

An enterprise with regional data-residency rules

→ GPT-5.4 Nano or LongCat-2.5

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

GPT-5.4 Nano: where it fits

OpenAI's cheapest GPT-5.4 variant at $0.20/$1.25 with a 400K window — a speed-and-cost tier for high-volume tasks, not deep reasoning. Released March 17, 2026 by OpenAI, it is built for cheapest GPT-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work, classification, extraction, ranking and sub-agent execution at scale, a 400K context in the smallest, fastest GPT-5.4 variant, and text and image input for cheap multimodal pipelines.

Its trade-offs are real: a nano tier — not built for hard reasoning or frontier coding, no published SWE-Bench Verified score (OpenAI reported SWE-Bench Pro instead), outclassed by GPT-5.4 and GPT-5.4 Mini whenever a task needs real depth, and image input only — no audio or video. At $0.2 in / $1.25 out per million tokens, it sits in the budget price band.

LongCat-2.5: where it fits

Meituan's November 2, 2026 natively multimodal successor to LongCat-2.0 - 1.6T parameters and 1M context at $0.30/$1.20, with open weights planned but undated. Released November 2, 2026 by Meituan, it is built for native multimodal upgrade to LongCat-2.0 - 1.6T total parameters, about 48B active per token, limited-time API price of $0.30/$1.20 per million tokens (cached input $0.006), meituan-reported Terminal-Bench v2.1 of 88.4, up from 70.8 for LongCat-2.0, and openAI- and Anthropic-compatible API endpoints with a 1M-token context window.

Its trade-offs: aPI-only for now - GitHub and Hugging Face releases are planned but undated, and the license is unconfirmed (LongCat-2.0 is MIT), the $0.30/$1.20 rate is labeled limited-time, and Meituan says prices are subject to change, and benchmarks are Meituan's own, and sources found no independent score at launch. At $0.3 in / $1.2 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." GPT-5.4 Nano (US) and LongCat-2.5 (China) differ on pricing philosophy, data-residency, and tooling as much as on raw scores. GPT-5.4 Nano 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 GPT-5.4 Nano and LongCat-2.5 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 GPT-5.4 Nano or LongCat-2.5 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, GPT-5.4 Nano leans toward cheapest gpt-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work while LongCat-2.5 leans toward native multimodal upgrade to longcat-2.0 - 1.6t total parameters, about 48b active per token, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, GPT-5.4 Nano or LongCat-2.5?

GPT-5.4 Nano is cheaper — $0.2/$1.25 per 1M tokens vs $0.3/$1.2 per 1M tokens, roughly 1.5× apart on input.

Which has the bigger context window?

LongCat-2.5 — 1M tokens vs 400K, about 2.5× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both GPT-5.4 Nano and LongCat-2.5 together?

Yes — a multi-model platform like LumiChats gives you GPT-5.4 Nano, LongCat-2.5 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, GPT-5.4 Nano or LongCat-2.5?

LongCat-2.5 — released November 2, 2026, about 8 months after GPT-5.4 Nano.

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.