Claude Opus 4.7 vs Solar Pro 4
Pricing, context window and real answers (August 2026)
Claude Opus 4.7 (Anthropic) and Solar Pro 4 (Upstage), 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 | Solar Pro 4 | |
|---|---|---|
| Provider | Anthropic | Upstage |
| Input (per 1M tokens) | ¥840 | ¥5.28 |
| Output (per 1M tokens) | ¥4,200 | ¥21.11 |
| Typical cost (1,000 in + 500 out tokens × 1,000 calls) | ¥2,940 | ¥16 |
| Context window | 1,000,000 tokens | 524,288 tokens |
| Release date | 4/16/2026 | 8/10/2026 |
| Input modalities | text, image, file | text |
| Arena · overall | #6 · ELO 1,494 | #173 · ELO 1,376 |
| Arena · Japanese | #18 · ELO 1,478 | Unranked |
| Arena · coding | #4 · ELO 1,547 | #140 · ELO 1,448 |
Prices are FastMetal's yen rates before tax. Arena ranks are as of the latest leaderboard scrape.
Which should you pick?
- On price, Solar Pro 4: ¥21.11 per 1M output tokens, 99% less than Claude Opus 4.7.
- On the Overall arena board, Claude Opus 4.7 ranks higher (#6; Solar Pro 4 is #173).
- On the Coding arena board, Claude Opus 4.7 ranks higher (#4; Solar Pro 4 is #140).
- For long documents, Claude Opus 4.7: a 1,000,000-token context window against 524,288 for Solar Pro 4.
- 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 Solar Pro 4?
- Per 1M output tokens, Claude Opus 4.7 is ¥4,200 and Solar Pro 4 is ¥21.11 on FastMetal (yen, before tax), so Solar Pro 4 is cheaper.
- How do the context windows of Claude Opus 4.7 and Solar Pro 4 compare?
- Claude Opus 4.7 takes 1,000,000 tokens; Solar Pro 4 takes 524,288.
- Which ranks higher, Claude Opus 4.7 or Solar Pro 4?
- Claude Opus 4.7 ranks higher on the public arena (Claude Opus 4.7 #18, Solar Pro 4 #173). Ranks move as the leaderboard updates.
- Can I use Claude Opus 4.7 and Solar Pro 4 with the same API key?
- Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "anthropic-claude-opus-4-7" or "solar-pro4" 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 Solar Pro 4 from the browser chat and the API. No monthly fee.