Claude Opus 4.7 Fast Mode Deprecated: What Changes on July 24, and How to Migrate

Anthropic deprecated fast mode for Claude Opus 4.7 on June 25, 2026. Removal is scheduled for July 24, 2026. After that date, any API request to claude-opus-4-7 with speed: "fast" will return an error — it will not silently fall back to standard Opus 4.7 or to any other model.

We also had a separate, later article on this same Opus 4.7 fast-mode removal, published July 15 and sourced only to third-party pricing blogs rather than Anthropic directly — it repeated a pricing-table error (standard pricing listed as $15/$75 for both models) that this page’s own claim-by-claim audit caught and fixed. That article has been retired and its URL now redirects here.

The migration is one line of code, and it comes with a price cut: Opus 4.8 fast mode costs $10/$50 per million tokens input/output, versus $30/$150 on Opus 4.7 fast mode (independently confirmed — Anthropic’s own docs no longer show the retired price after removal). That is a 3x reduction.

Also worth knowing: Claude Opus 5 launched July 24, 2026 — the same day fast mode on Opus 4.7 was removed — and it supports fast mode at the identical $10/$50 pricing. Opus 4.8 remains available on all of the same platforms, so it is still a valid migration target, but if you’re migrating today, evaluate Opus 5 too rather than assuming Opus 4.8 is still the newest option.

What Fast Mode Actually Does

Fast mode is a premium runtime option that trades higher per-token price for up to 2.5x higher output tokens per second. You enable it by setting speed: "fast" alongside the fast-mode-2026-02-01 beta header.

The use cases it fits: real-time streaming interfaces where latency per token matters more than cost, multi-agent pipelines where a fast synthesis step unblocks downstream work, and any workload where a human is waiting on the response.

The Breaking Change on July 24

This is a hard removal, not a deprecation warning:

• Before July 24: speed: "fast" on Opus 4.7 continues to work
• After July 24: speed: "fast" on Opus 4.7 returns an error
• After July 24: there is no automatic fallback to standard Opus 4.7

If your production code calls claude-opus-4-7 with speed: "fast" and you have not migrated, you will see request failures starting July 24.

This also applies inside Claude Code: Anthropic’s docs confirm that Claude Code treats Opus 4.7 as a fast-mode model everywhere it decides whether fast mode is on — the /fast toggle, model switches in either direction, and session start — and “the API rejects the resulting fast mode requests rather than serving them at standard speed.” If your session’s saved model is pinned to claude-opus-4-7 with fast mode on, switch the pinned model to keep the speedup.

The Migration

Change the model ID and nothing else. The beta header and speed parameter syntax are identical on Opus 4.8.

Before:

response = client.beta.messages.create(
    model="claude-opus-4-7",
    max_tokens=4096,
    speed="fast",
    betas=["fast-mode-2026-02-01"],
    messages=[{"role": "user", "content": "..."}],
)

After:

response = client.beta.messages.create(
    model="claude-opus-4-8",
    max_tokens=4096,
    speed="fast",
    betas=["fast-mode-2026-02-01"],
    messages=[{"role": "user", "content": "..."}],
)

One change: claude-opus-4-7 → claude-opus-4-8.

Note: Fast mode on Opus 4.8 is currently a research preview. If you do not already have access, contact your Anthropic account manager, or join the waitlist if you don’t have one, to enable it on your account before July 24.

Pricing Comparison

Standard pricing did not change between Opus 4.7 and Opus 4.8 — both are $5/$25 per million input/output tokens, the same rate Anthropic has held since Opus 4.6. What changed is the size of the fast-mode markup: Opus 4.7 fast mode charged a 6x premium over its own standard rate, while Opus 4.8 fast mode charges only a 2x premium over its own standard rate ($10 vs. $5 input, $50 vs. $25 output). Fast mode is still pricier than standard mode on both models — it is never the cheaper option — but Anthropic shrank the size of that premium when it shipped fast mode for Opus 4.8.

For a workload running 100M output tokens per month on Opus 4.7 fast, the switch to Opus 4.8 fast drops monthly output cost from $15,000 to $5,000.

What Opus 4.8 Adds Beyond Speed

Migration is not purely a defensive move. Opus 4.8 (released May 28, 2026) ships additional capabilities beyond speed:

• Dynamic Workflows: in Claude Code, Opus 4.8 can plan out a large task and then run hundreds of parallel subagents in a single session to execute it, verifying its outputs before reporting back — a research preview available on Claude Code Enterprise, Team, and Max plans
• Effort defaults to high everywhere: the effort parameter now defaults to high across the Claude API, Claude Code, and claude.ai — the effort ladder itself (low through xhigh) shipped earlier, on Opus 4.7
• Lower rate of misaligned behavior: Anthropic’s own safety evaluation found Opus 4.8’s rate of misaligned behavior (deception or cooperation with misuse) is “substantially lower than Opus 4.7, and similar to our best-aligned model, Claude Mythos Preview”

Note what did not change: the 1M token context window carried over unchanged from Opus 4.7, which introduced it on April 16, 2026 — Opus 4.8 did not raise it. If your existing Opus 4.7 fast workloads are simple generation tasks, you likely will not need Dynamic Workflows immediately, and there’s no context-window gain to chase. The lower misalignment rate and the effort-default change apply automatically once you migrate, with no code change required beyond the model ID.

Checklist Before July 24

1. Audit API calls: grep your codebase for claude-opus-4-7 to find all call sites; separately grep for fast-mode-2026-02-01 to find any non-Opus 4.7 calls that use fast mode
2. Confirm Opus 4.8 fast access: if you do not see fast-mode-2026-02-01 working on Opus 4.8 in your account, contact your account manager now — the research preview is not automatically enabled
3. Update model ID: one-line change per call site
4. Update cost estimates: your fast-mode budget should decrease by roughly 3x; update forecasting if it is in your billing model
5. Test before deadline: run your staging workload on Opus 4.8 fast before July 24 to catch any behavioral differences

Timeline

That is 26 days from today. The migration itself takes minutes. The lead time is for testing, access confirmation, and updating downstream cost tracking.