Sweep 22 Sep 2026 · 17:19Z Build v2.1.280 501 read Stable v2.1.267 Latest v2.1.280 Next v2.1.280 Feeds RSS JSON llms.txt Unofficial
One change · claude-code

Speed up responses with fast mode changed

fast-mode

Nearest release: v2.1.280, published under an hour before upstream edited the page. Shown because the two are within 24 hours of each other. Nothing here says the release caused the edit.

Upstream edited this page at 22 Sep 2026 16:28 UTC, give or take a minute or two: the time comes from Anthropic’s own sitemap rather than from a commit. This site recorded the change at 22 Sep 2026 16:37 UTC.

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99Fast mode is a high-speed configuration for Claude Opus, making the model up to 2.5x faster at a higher cost per token. Toggle it on with `/fast` when you need speed for interactive work like rapid iteration or live debugging, and toggle it off when cost matters more than latency.
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11Fast mode is not a different model. It uses Claude Opus with a different API configuration that prioritizes speed over cost efficiency. You get identical quality and capabilities with faster responses. Fast mode is supported on Opus 5 and Opus 4.8. It is not available on Sonnet, Haiku, or other models.
11Fast mode is not a different model. It uses Claude Opus with a different API configuration that prioritizes speed over cost efficiency. You get identical quality and capabilities with faster responses. Fast mode is supported on Opus 5.5, Opus 5, and Opus 4.8. It is not available on Sonnet, Haiku, or other models.
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1313Opus 4.7 doesn't support fast mode, so switching to it turns fast mode off. Fast mode for Opus 4.7 was deprecated on June 25, 2026, and removed on July 24, 2026.
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1515What to know:
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1717* Use `/fast` to toggle on fast mode in the Claude Code CLI. The [VS Code extension](/docs/en/vs-code) offers a **Toggle fast mode** command when the selected model supports fast mode. Claude Code saves that toggle to your [`fastMode` setting](#toggle-fast-mode).
18* Fast mode pricing per MTok input/output is \$10/\$50 on Opus 5 and Opus 4.8.
18* Fast mode pricing per MTok input/output is \$8/\$40 on Opus 5.5 and \$10/\$50 on Opus 5 and Opus 4.8.
1919* Available to Claude Code users on subscription plans (Pro/Max/Team/Enterprise) and on Claude Console. Team and Enterprise organizations need an Owner to enable it first, and Console organizations need access provisioned first, both described under [Requirements](#requirements).
2020* For Claude Code users on subscription plans (Pro/Max/Team/Enterprise), fast mode is available via usage credits only and not included in the subscription rate limits.
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4141* A small `↯` icon appears next to the prompt while fast mode is active
4242* Run `/fast` again at any time to check whether fast mode is on or off
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44Opus 5 is the fast mode default in Claude Code v2.1.219 and later. Before v2.1.219, fast mode defaulted to Opus 4.8 on v2.1.154 through v2.1.218, and to Opus 4.7 on v2.1.142 through v2.1.153.
44Opus 5.5 is the fast mode default in Claude Code v2.1.280 and later. Before v2.1.280, fast mode defaulted to Opus 5 from v2.1.219, to Opus 4.8 on v2.1.154 through v2.1.218, and to Opus 4.7 on v2.1.142 through v2.1.153.
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4646When you disable fast mode with `/fast` again, you remain on Opus. To switch to a different model, use `/model`.
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6969| Model | Input (MTok) | Output (MTok) |
7070| -------- | ------------ | ------------- |
71| Opus 5.5 | \$8 | \$40 |
7172| Opus 5 | \$10 | \$50 |
7273| Opus 4.8 | \$10 | \$50 |
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