GPT-5.1 vs Palmyra X6

OpenAI · US  |  Writer · US · Updated June 2026

Quick verdict

Pick GPT-5.1 for adaptive reasoning that scales compute to task difficulty or general-purpose reasoning, coding and tool use. Pick Palmyra X6 for enterprise agentic workflows - built specifically for marketing/revenue teams running multi-step agents or writer says its harness upgrades cut agent-workflow token costs by roughly 52% and improve speed by roughly 48% (writer's own figures). On a tight budget at scale, Palmyra X6 is the value pick.

GPT-5.1 (OpenAI) and Palmyra X6 (Writer) are two of the models people most often weigh against each other in 2026. GPT-5.1 is openAI's late-2025 GPT-5.1 at $1.25/$10 — a capable general model since surpassed by the GPT-5.2–5.6 line. Palmyra X6 is writer's enterprise agentic flagship - a GLM-5.2-based model with harness upgrades Writer says cut agent token costs by roughly half. 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-5.1Palmyra X6
ProviderOpenAI (US) Writer (US)
ReleasedNovember 13, 2025 August 13, 2026
Context window400K (~600 pages) 128K (~192 pages)
Price (in/out)$1.25/$10 per 1M tokens Not published
Open weight?No — API only No — API only
Modalitiestext, image, code text, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Adaptive reasoning that scales compute to task difficulty

GPT-5.1

OpenAI's late-2025 GPT-5.1 at $1.25/$10 — a capable general model since surpassed by the GPT-5.2–5.6 line — and it carries the larger 400K context.

General-purpose reasoning, coding and tool use

GPT-5.1

Palmyra X6 is comparatively weak here — not independently benchmarked on general leaderboards like SWE-bench or Artificial Analysis

A large ~400K context for long documents and sessions

GPT-5.1

Its 400K window holds about 3.1× more than Palmyra X6's 128K in a single prompt.

Enterprise agentic workflows - built specifically for marketing/revenue teams running multi-step agents

Palmyra X6

Writer's enterprise agentic flagship - a GLM-5.2-based model with harness upgrades Writer says cut agent token costs by roughly half — and it is the newer of the two.

Writer says its harness upgrades cut agent-workflow token costs by roughly 52% and improve speed by roughly 48% (Writer's own figures)

Palmyra X6

Palmyra X6 lists writer says its harness upgrades cut agent-workflow token costs by roughly 52% and improve speed by roughly 48% (Writer's own figures) among its strengths; GPT-5.1 does not.

A post-trained variant built on Z.ai's open-weight GLM-5.2, tuned specifically for business agent use

Palmyra X6

Palmyra X6 lists a post-trained variant built on Z.ai's open-weight GLM-5.2, tuned specifically for business agent use among its strengths; GPT-5.1 does not.

Lowest cost at scale

Palmyra X6

Its weights are open, so at volume you pay for your own hardware instead of GPT-5.1's $1.25/$10 per 1M tokens.

Largest single-prompt input

GPT-5.1

Its 400K window is about 3.1× larger than Palmyra X6's 128K, fitting roughly 600 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

Palmyra X6

At Not published it undercuts GPT-5.1, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

GPT-5.1

Larger 400K window fits more in one prompt.

Anyone whose priority is adaptive reasoning that scales compute to task difficulty

GPT-5.1

It is specifically built for that.

Anyone whose priority is enterprise agentic workflows - built specifically for marketing/revenue teams running multi-step agents

Palmyra X6

That is its strongest area.

GPT-5.1: where it fits

OpenAI's late-2025 GPT-5.1 at $1.25/$10 — a capable general model since surpassed by the GPT-5.2–5.6 line. Released November 13, 2025 by OpenAI, it is built for adaptive reasoning that scales compute to task difficulty, general-purpose reasoning, coding and tool use, a large ~400K context for long documents and sessions, and text and image input.

Its trade-offs are real: superseded by GPT-5.2 through GPT-5.6 — kept for compatibility rather than being current, no reliably published SWE-Bench Verified figure, exact context window unconfirmed (400K vs 410K across trackers), and premium output price at $10/1M for a now-older model. At $1.25 in / $10 out per million tokens, it sits in the mid price band.

Palmyra X6: where it fits

Writer's enterprise agentic flagship - a GLM-5.2-based model with harness upgrades Writer says cut agent token costs by roughly half. Released August 13, 2026 by Writer, it is built for enterprise agentic workflows - built specifically for marketing/revenue teams running multi-step agents, writer says its harness upgrades cut agent-workflow token costs by roughly 52% and improve speed by roughly 48% (Writer's own figures), and a post-trained variant built on Z.ai's open-weight GLM-5.2, tuned specifically for business agent use.

Its trade-offs: no public per-token API price - sold through Writer's enterprise platform, not a self-serve API, not independently benchmarked on general leaderboards like SWE-bench or Artificial Analysis, and built for a narrower enterprise-agent use case rather than general-purpose chat.

The bottom line for this matchup

GPT-5.1 and Palmyra X6 overlap enough that the right pick depends on your specific job. Palmyra X6 costs less per token; GPT-5.1 holds the larger context; and each leads in its own area — GPT-5.1 for adaptive reasoning that scales compute to task difficulty, Palmyra X6 for enterprise agentic workflows - built specifically for marketing/revenue teams running multi-step agents. Rather than crowning one, run the same hard task through both once and let the results decide.

Want both GPT-5.1 and Palmyra X6 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-5.1 or Palmyra X6 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-5.1 leans toward adaptive reasoning that scales compute to task difficulty while Palmyra X6 leans toward enterprise agentic workflows - built specifically for marketing/revenue teams running multi-step agents, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, GPT-5.1 or Palmyra X6?

Palmyra X6 is cheaper — $1.25/$10 per 1M tokens vs Not published.

Which has the bigger context window?

GPT-5.1 — 400K vs 128K, about 3.1× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both GPT-5.1 and Palmyra X6 together?

Yes — a multi-model platform like LumiChats gives you GPT-5.1, Palmyra X6 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-5.1 or Palmyra X6?

Palmyra X6 — released August 13, 2026, about 9 months after GPT-5.1.

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.