Model comparison

Claude Haiku 4.5 vs GLM 5.3

Pricing, context window and real answers (August 2026)

Claude Haiku 4.5 (Anthropic) and GLM 5.3 (Z.ai), compared as you can actually call them on FastMetal. Both are served from the same OpenAI-compatible endpoint and API key; switching is a change to the model string.

Specs and pricing

anthropic logoClaude Haiku 4.5z-ai logoGLM 5.3
ProviderAnthropicZ.ai
Input (per 1M tokens)¥184.8¥250.18
Output (per 1M tokens)¥924¥786.28
Typical cost (1,000 in + 500 out tokens × 1,000 calls)¥647¥643
Context window200,000 tokens1,048,576 tokens
Release date10/15/20258/18/2026
Input modalitiesimage, texttext
Arena · overall#120 · ELO 1,412Unranked
Arena · Japanese#99 · ELO 1,355Unranked
Arena · coding#86 · ELO 1,479Unranked

Prices are FastMetal's yen rates before tax. Arena ranks are as of the latest leaderboard scrape.

Which should you pick?

  • On price, GLM 5.3: ¥786.28 per 1M output tokens, 15% less than Claude Haiku 4.5.
  • For long documents, GLM 5.3: a 1,048,576-token context window against 200,000 for Claude Haiku 4.5.
  • If in doubt, try both on the same key. Switching is a change to the model string, and each is billed at its own rate.

Real answers to the same prompts

Exactly what the FastMetal gateway returned, side by side. Not benchmark scores: actual output.

Count the number of 'r's in 'strawberry'

Count the number of 'r's in 'strawberry'. Explain your reasoning step by step.

Claude Haiku 4.5

# Counting the 'r's in "strawberry" Let me go through each letter in the word "strawberry": 1. **s** - not an 'r' 2. **t** - not an 'r' 3. **r** - this is an 'r' ✓ (1st) 4. **a** - not an 'r' 5. **w** - not an 'r' 6. **b** - not an 'r' 7. **e** - not an 'r' 8. **r** - this is an 'r' ✓ (2nd) 9. **r** - this is an 'r' ✓ (3rd) 10. **y** - not an 'r' **Answer: There are 3 'r's in "strawberry"** The 'r's appear in positions 3, 8, and 9 of the word.
4.1s228 output tokens

GLM 5.3

# Counting 'r's in "strawberry" **Step 1: Spell out the word letter by letter.** s - t - r - a - w - b - e - r - r - y **Step 2: Go through each letter and mark the 'r's.** | Position | Letter | Is it 'r'? | |----------|--------|------------| | 1 | s | No | | 2 | t | No | | 3 | **r** | ✅ Yes (1st) | | 4 | a | No | | 5 | w | No | | 6 | b | No | | 7 | e | No | | 8 | **r** | ✅ Yes (2nd) | | 9 | **r** | ✅ Yes (3rd) | | 10 | y | No | **Step 3: Tally the results.** - 1st 'r' in "st**r**awberry" - 2nd 'r' in "strawbe**r**ry" - 3rd 'r' in "strawber**r**y" ## Answer: There are **3** 'r's in "strawberry." (Note: two of them appear together in the "rr" near the end, which is easy to miss when c…
5.8s493 output tokens

Debug This Error

I'm getting the following error in my Node.js application: TypeError: Cannot read properties of undefined (reading 'map') at UserList (/app/components/UserList.js:12:25) at renderWithHooks (/app/node_modules/rea…

Claude Haiku 4.5

# TypeError: Cannot read properties of undefined (reading 'map') This error occurs because `users` is `undefined` when the component renders. You're trying to call `.map()` on `undefined`, which doesn't have that method. ## Common Causes 1. **Parent component didn't pass the `users` prop** 2. **Async data hasn't loaded yet** 3. **Props passed incorrectly** ## Solutions ### 1. **Provide a Default Value** (Recommended) ```javascript function UserList({ users = [] }) { return ( <ul> {users.map(user => <li key={user.id}>{user.name}</li>)} </ul> ); } ``` ### 2. **Add a Conditional Check** ```javascript function UserList({ users }) { if (!users) { return <p>No users a…
3.9s671 output tokens

GLM 5.3

## What's happening The error means `users` is `undefined` when the component renders. `undefined` doesn't have a `.map()` method, so JavaScript throws a `TypeError`. Since destructured props that aren't passed default to `undefined`, something upstream isn't providing the value you expect. ## Common causes 1. **The parent doesn't pass the prop, or uses a different name:** ```jsx <UserList /> {/* missing users */} <UserList userList={users} /> {/* prop name mismatch */} ``` 2. **Async data hasn't loaded yet** — the component renders before an API call completes, and the initial value is `undefined`: ```jsx const [users, setUsers] = useState(); // undefin…
17.1s1345 output tokens

Code Review

Please review the following Python function and suggest improvements for readability, performance, and best practices: def get_data(url, retries=3): import requests import time for i in range(retries):…

Claude Haiku 4.5

# Code Review and Improvements ## Issues Found 1. **Bare `except`** - Catches all exceptions, hiding bugs 2. **Imports inside function** - Should be at module level 3. **Redundant comparison** - `== True` is unnecessary 4. **No logging** - Hard to debug failures 5. **Magic numbers** - Hardcoded timeout and sleep values 6. **Inefficient retries** - Doesn't retry on 200 with parsing errors 7. **Poor variable names** - `r`, `i` are unclear 8. **No type hints** - Reduces code clarity ## Improved Version ```python import logging import requests import time from typing import Optional from requests.exceptions import RequestException logger = logging.getLogger(__name__) def get_data( url:…
5.7s988 output tokens

GLM 5.3

Here's a breakdown of the issues, followed by a refactored version. ## Readability - **Move imports to module level.** PEP 8 requires top-level imports; importing inside a function hides dependencies and adds overhead on every call (small, but pointless). - **`item["active"] == True`** → just `item.get("active")`. Comparing to `True` with `==` is flagged by PEP 8, and `.get()` avoids a `KeyError` if the key is missing. - **Use a list comprehension** instead of initializing a list and appending in a loop. - **Rename things.** `get_data` doesn't say what it does (`fetch_active_items`?), and `response` beats `r`. Use `_` for the unused loop counter. - **Magic numbers** (`2`, `10`) should be n…
75.0s6434 output tokens

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Frequently asked questions

Which is cheaper, Claude Haiku 4.5 or GLM 5.3?
Per 1M output tokens, Claude Haiku 4.5 is ¥924 and GLM 5.3 is ¥786.28 on FastMetal (yen, before tax), so GLM 5.3 is cheaper.
How do the context windows of Claude Haiku 4.5 and GLM 5.3 compare?
Claude Haiku 4.5 takes 200,000 tokens; GLM 5.3 takes 1,048,576.
Can I use Claude Haiku 4.5 and GLM 5.3 with the same API key?
Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "anthropic-claude-haiku-4-5" or "glm-5.3" as the model. Each is billed at its own rate from the same prepaid balance.

Try both on one API key

Create an account and add credit to call Claude Haiku 4.5 and GLM 5.3 from the browser chat and the API. No monthly fee.

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