Claude Haiku 4.5 (2025-10-01) vs Glm 5.1

Claude Haiku 4.5 (2025-10-01) (Anthropic, 200,000-token context) versus Glm 5.1 (Z.ai, 200,000-token context). Glm 5.1 is cheaper by 3% on a blended token mix. Claude Haiku 4.5 (2025-10-01) uniquely supports vision input and pdf input. Use the live calculator below to plug your real usage shape into both, then route the winner via Agent Command Center for shadow A/B without code changes.

Bottom line — Claude Haiku 4.5 (2025-10-01) vs Glm 5.1

Claude Haiku 4.5 (2025-10-01) and Glm 5.1 are priced within 3% of each other, so cost alone is not the deciding factor. The comparison comes down to capabilities, context window, and benchmark performance on the specific task shape your workload demands.

On capability surface area, the models diverge: Claude Haiku 4.5 (2025-10-01) supports vision input where the other does not; Claude Haiku 4.5 (2025-10-01) supports pdf input where the other does not; Claude Haiku 4.5 (2025-10-01) supports structured output (json schema) where the other does not. These differences are binary — either your workload needs the capability or it does not. Check whether any critical path in your agent pipeline depends on a capability only one model provides before committing to a migration.

For teams evaluating both models, the recommended path is a shadow A/B test: route production traffic through an OpenAI-compatible gateway, mirror a percentage to the candidate model, score both responses with an automated evaluator (faithfulness, tool-call correctness, latency), and compare cohort-level metrics over two weeks. Future AGI Agent Command Center supports this pattern with a single `base_url` change and built-in evaluators from the ai-evaluation SDK.

Side-by-side cost

Live workload comparison

Same workload run through both models. The cheaper one is highlighted.

3,000
0200,000
400
0128,000
5,000
01,000,000
Anthropic
$761/mo
Input $1.00/M · Output $5.00/M
Z.ai
$907/mo
Input $1.40/M · Output $4.40/M
At this workload, Claude Haiku 4.5 (2025-10-01) is 16% cheaper than Glm 5.1 — a savings of $146/month ($1,753/year).
Crossover: Claude Haiku 4.5 (2025-10-01) is cheaper when output/input ≤ 0.67 (input-heavy workloads — RAG, retrieval). Glm 5.1 wins above (long-form generation).
Current workload ratio: 0.13 (400/3000)
Production recipe — Agent Command Center
strategy: cost-optimized
primary:
  model: claude-haiku-4-5-20251001
  provider: anthropic
fallback:
  model: glm-5-1
  provider: zai
shadow: { sample_rate: 0.05 }   # mirror 5% of traffic to compare quality live
Claude Haiku 4.5 (2025-10-01) Glm 5.1
Input price $1.00/M $1.40/M
Output price $5.00/M $4.40/M
Context window 200,000 200,000
Max output 64,000 128,000
Function calling
Vision
Audio input
Reasoning
Prompt caching
Structured output
Pricing verified Aug 6, 2026 Aug 6, 2026
Cheaper option
~3% cheaper than the priciest in this pair
Larger context
200,000 tokens
More capabilities
5 of 6 capability flags advertised

Benchmark comparison

Side-by-side public benchmark scores. Greener bar = winner.

Chatbot Arena ELOgeneral
Claude Haiku 4.5 (2025-10-01)
1,412
Glm 5.1
HumanEvalcode
Claude Haiku 4.5 (2025-10-01)
89.5%
Glm 5.1
BFCL v3agent
Claude Haiku 4.5 (2025-10-01)
79.3%
Glm 5.1
MMLU-Proreasoning
Claude Haiku 4.5 (2025-10-01)
72.4%
Glm 5.1
GPQA Diamondreasoning
Claude Haiku 4.5 (2025-10-01)
55.2%
Glm 5.1
SWE-bench Verifiedagent
Claude Haiku 4.5 (2025-10-01)
52.0%
Glm 5.1

Cost at scale: monthly spend at three usage volumes

Estimated monthly cost assuming 1,000 input + 200 output tokens per request — a realistic chat-agent shape. Adjust your own usage in the calculator at the top of this page for an exact number.

Scale Claude Haiku 4.5 (2025-10-01) Glm 5.1 Delta
Startup
10K requests/day
$600 /mo $684 /mo $84.00/mo
Mid-market
100K requests/day
$6,000 /mo $6,840 /mo $840/mo
Enterprise
1M requests/day
$60,000 /mo $68,400 /mo $8,400/mo

At enterprise scale (1M requests/day), a difference of even ~10% in unit price compounds into thousands of dollars per month. Cached input pricing and batch tiers can shift this further — both are surfaced on each model's own page.

When to choose which

Picked from the data above — not vendor marketing. Match the rules to your workload, not the other way around.

Choose Claude Haiku 4.5 (2025-10-01)

Your inputs include screenshots, diagrams, or product photos — Claude Haiku 4.5 (2025-10-01) accepts image input natively, the other doesn't.

Capability diff — what you gain and lose on the swap

A specific list of what each model has that the other doesn't. If your workload depends on a row in Only Claude Haiku 4.5 (2025-10-01), switching to Glm 5.1 means re-architecting that path (and vice versa).

Only on Claude Haiku 4.5 (2025-10-01)
  • • Vision input
  • • PDF input
  • • Structured output (JSON schema)
Only on Glm 5.1
Nothing — everything Glm 5.1 ships is also on Claude Haiku 4.5 (2025-10-01).
Capabilities both share (4)
  • ✓ Function calling
  • ✓ Streaming
  • ✓ Prompt caching
  • ✓ Native reasoning mode

Migration considerations

Concrete differences to wire through your stack before you flip traffic from one to the other.

  • Max output tokens differ: 64,000 on Claude Haiku 4.5 (2025-10-01) vs 128,000 on Glm 5.1. Long-form generation tasks may truncate differently — adjust streaming UI and chunking accordingly.
  • Claude Haiku 4.5 (2025-10-01) has capabilities Glm 5.1 lacks: Vision input, PDF input, Structured output (JSON schema). Switching to Glm 5.1 means re-architecting any flow that depends on these.
  • Provider changes from Anthropic to Z.ai. API authentication, rate-limit policy, regional availability, and billing all shift. Most teams route through an OpenAI-compatible gateway (e.g., Future AGI Agent Command Center) so the swap is a single `base_url` change instead of an SDK rewrite.

How to A/B test Claude Haiku 4.5 (2025-10-01) vs Glm 5.1 in production

If you're stuck between the two, run them side-by-side on real traffic. Four steps the Future AGI team uses internally:

  1. 1. Point your existing OpenAI SDK at https://gateway.futureagi.com/v1. No code change beyond base_url and a virtual key.
  2. 2. Mark Claude Haiku 4.5 (2025-10-01) primary, mirror 20% of traffic to Glm 5.1 in shadow mode. Both responses are logged; only the primary is served to users.
  3. 3. Score every shadow response with an evaluator — faithfulness, tool-call correctness, response latency, cost. Built-in evaluators in ai-evaluation cover the common axes.
  4. 4. Compare cohort-level metrics after two weeks. Switch primary when the candidate wins on what matters to your workload — and stays within your latency budget.

Full walkthrough on the Agent Command Center page.

FAQ — Claude Haiku 4.5 (2025-10-01) vs Glm 5.1

Which is cheaper, Claude Haiku 4.5 (2025-10-01) or Glm 5.1?

Glm 5.1 is cheaper by roughly 3% on a blended input + output token mix. Input prices are $1.00/M for Claude Haiku 4.5 (2025-10-01) versus $1.40/M for Glm 5.1; output prices are $5.00/M versus $4.40/M. The exact savings depend on your input:output ratio — use the live calculator above to plug in your own request shape.

What is the context window of Claude Haiku 4.5 (2025-10-01) versus Glm 5.1?

Claude Haiku 4.5 (2025-10-01) supports up to 200,000 tokens of context. Glm 5.1 supports up to 200,000 tokens. Glm 5.1 has the larger window by a factor of 1.0x, which matters for long-document RAG, multi-turn agent sessions, and tasks that need to keep an entire codebase in working memory.

Do Claude Haiku 4.5 (2025-10-01) and Glm 5.1 both support tool calling?

Yes — both Claude Haiku 4.5 (2025-10-01) and Glm 5.1 support native function calling. Both also support structured output via JSON schema, so an agent can be ported between them with the same tool definitions.

Can Claude Haiku 4.5 (2025-10-01) and Glm 5.1 process images?

Claude Haiku 4.5 (2025-10-01) accepts native image input. Glm 5.1 does not — you would need to route image-heavy workloads through Claude Haiku 4.5 (2025-10-01) or add a separate vision model in front of Glm 5.1.

Which model supports prompt caching for cost reduction?

Both Claude Haiku 4.5 (2025-10-01) and Glm 5.1 support prompt caching. Cached input tokens are typically discounted 50–90% versus uncached input, depending on the provider. For agents with a stable system prompt + retrieval context, the cached pricing tier is the real unit economics number to track.

How do I A/B test Claude Haiku 4.5 (2025-10-01) against Glm 5.1 in production?

Route both through an OpenAI-compatible gateway like Future AGI Agent Command Center with shadow mode enabled. Send 100% of traffic to your primary model, mirror 10–20% to the candidate, score every response with an evaluator (faithfulness, tool-call correctness, response time), and compare cohort-level metrics for two weeks. Switch when the candidate wins on the metrics that matter to your workload and stays within your latency budget.