Claude Opus 4.7 vs LLM-jp-3.1 8x13B instruct4
Pricing, context window and real answers (August 2026)
Claude Opus 4.7 (Anthropic) and LLM-jp-3.1 8x13B instruct4 (Llm Jp), 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
 Claude Opus 4.7 | LLM-jp-3.1 8x13B instruct4 | |
|---|---|---|
| Provider | Anthropic | Llm Jp |
| Input (per 1M tokens) | ¥840 | ¥16 |
| Output (per 1M tokens) | ¥4,200 | ¥79 |
| Typical cost (1,000 in + 500 out tokens × 1,000 calls) | ¥2,940 | ¥56 |
| Context window | 1,000,000 tokens | 4,096 tokens |
| Release date | 4/16/2026 | 3/21/2026 |
| Input modalities | text, image, file | text |
| Arena · overall | #6 · ELO 1,494 | Unranked |
| Arena · Japanese | #18 · ELO 1,478 | Unranked |
| Arena · coding | #4 · ELO 1,547 | Unranked |
Prices are FastMetal's yen rates before tax. Arena ranks are as of the latest leaderboard scrape.
Which should you pick?
- On price, LLM-jp-3.1 8x13B instruct4: ¥79 per 1M output tokens, 98% less than Claude Opus 4.7.
- For long documents, Claude Opus 4.7: a 1,000,000-token context window against 4,096 for LLM-jp-3.1 8x13B instruct4.
- 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.
Frequently asked questions
- Which is cheaper, Claude Opus 4.7 or LLM-jp-3.1 8x13B instruct4?
- Per 1M output tokens, Claude Opus 4.7 is ¥4,200 and LLM-jp-3.1 8x13B instruct4 is ¥79 on FastMetal (yen, before tax), so LLM-jp-3.1 8x13B instruct4 is cheaper.
- How do the context windows of Claude Opus 4.7 and LLM-jp-3.1 8x13B instruct4 compare?
- Claude Opus 4.7 takes 1,000,000 tokens; LLM-jp-3.1 8x13B instruct4 takes 4,096.
- Can I use Claude Opus 4.7 and LLM-jp-3.1 8x13B instruct4 with the same API key?
- Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "anthropic-claude-opus-4-7" or "llm-jp-3.1-8x13b-instruct4" 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 Opus 4.7 and LLM-jp-3.1 8x13B instruct4 from the browser chat and the API. No monthly fee.