API cost decision in 10 seconds

GLM 5.1 vs Palmyra X5

Pick GLM 5.1 for lower cost; pick Palmyra X5 only if the larger context window matters more.

Page updated: 2026-05-26T10:03:26Z Data confirmed: 2026-05-26T13:08:02Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick GLM 5.1 for lower cost; pick Palmyra X5 only if the larger context window matters more.

On the standard 1M input plus 500K output workload, GLM 5.1 is estimated at $2.52 vs $3.6 for Palmyra X5, saving $1.08 (30% lower).

Cost-first pickGLM 5.1

Context-first pickPalmyra X5

Sample savings$1.0830%

10x traffic gap$10.8

Palmyra X5 has more context, but GLM 5.1 saves $1.08 on the standard workload. At 10x that traffic, the same price gap is about $10.8. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

Cost winner changes by workload shape: input-heavy / RAG favors Palmyra X5, balanced workload favors GLM 5.1, and output-heavy chatbot favors GLM 5.1.

Workload shape	Token mix	Better pick	GLM 5.1	Palmyra X5
Input-heavy / RAG	5M input + 500K output	Palmyra X5	$6.44	$6
Balanced workload	1M input + 1M output	GLM 5.1	$4.06	$6.6
Output-heavy chatbot	1M input + 5M output	GLM 5.1	$16.38	$30.6

Cheaper input Palmyra X5 $0.98 vs $0.6 / 1M

Palmyra X5 is $0.38 cheaper per 1M input tokens (38.8% lower; 1.63x difference).

Cheaper output GLM 5.1 $3.08 vs $6 / 1M

GLM 5.1 is $2.92 cheaper per 1M output tokens (48.7% lower; 1.95x difference).

Larger context Palmyra X5 202.75K vs 1.04M

Palmyra X5 has 837.25K more context (5.13x larger).

Sample workload GLM 5.1 $2.52 vs $3.6

GLM 5.1 is $1.08 cheaper on the standard workload (30% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

GLM 5.1 Calculating… Estimated API cost

Palmyra X5 Calculating… Estimated API cost

Cheaper for this workload Calculating… Difference: calculating…

This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.

Quick Decision

Verdict

Palmyra X5 has the lower input price; GLM 5.1 has the lower output price; Palmyra X5 offers the larger context window. For the 1M input plus 500K output sample, GLM 5.1 is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $2.52 for GLM 5.1 and $3.6 for Palmyra X5.

Best Fit

Choose GLM 5.1 when you care most about lower output-token price.

Choose Palmyra X5 when you care most about lower input-token price, and larger context window.

Decision Notes

On the standard 1M input plus 500K output workload, GLM 5.1 is estimated at $2.52 vs $3.6 for Palmyra X5, saving $1.08 (30% lower).
GLM 5.1 is $1.08 cheaper on the standard workload (30% lower).
Palmyra X5 is $0.38 cheaper per 1M input tokens (38.8% lower; 1.63x difference).
GLM 5.1 is $2.92 cheaper per 1M output tokens (48.7% lower; 1.95x difference).
Palmyra X5 has 837.25K more context (5.13x larger).

Head-to-Head Specs

Feature	GLM 5.1 (Z.ai)	Palmyra X5 (Writer)
Input Price prompt tokens per 1M	$0.98	$0.6
Completion Price per 1M tokens	$3.08	$6
Sample Workload Cost 1M input + 500K output	$2.52	$3.6
Context Window	202.75K	1.04M
Release Date	2026-04-07	2026-01-21

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	GLM 5.1	On the standard 1M input plus 500K output workload, GLM 5.1 is estimated at $2.52 vs $3.6 for Palmyra X5, saving $1.08 (30% lower).
High-volume input processing	Palmyra X5	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	GLM 5.1	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	Palmyra X5	A larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps

GLM 4.5 Air (free) can replace GLM 5.1 when lower sample workload cost matters most: $0.
GLM 4 32B can replace GLM 5.1 when lower sample workload cost matters most: $0.15.
GLM 4.7 Flash can replace GLM 5.1 when lower sample workload cost matters most: $0.26.
GLM 4.5 Air can replace GLM 5.1 when lower sample workload cost matters most: $0.55.

Larger context near this budget

Llama 4 Scout offers 10M context with $0.23 sample workload cost.
Grok 4.20 offers 2M context with $2.5 sample workload cost.
Owl Alpha offers 1.05M context with $0 sample workload cost.
DeepSeek V4 Flash offers 1.05M context with $0.2 sample workload cost.

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Provider catalogs

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Z.ai catalog

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Writer catalog

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