Claude Opus 4.8 fast mode is now in preview for GitHub Copilot, announced in GitHub's changelog on 2026-06-29. It is the same model as standard Claude Opus 4.8 - same intelligence, same quality - tuned for significantly faster output, available on paid Copilot tiers.
What fast mode is
Fast mode is not a different, weaker model. It is Claude Opus 4.8 optimized for output token speed: you get significantly faster responses with the same intelligence and quality as the standard model. Standard Claude Opus 4.8 has been generally available in GitHub Copilot since 2026-05-28; this preview simply adds the speed-optimized variant. If you have used standard Opus 4.8, fast mode should feel identical in answers - just quicker.
The distinction matters because speed and capability are usually presented as a trade-off - a "smaller, faster" model is normally a less capable one. Here that is not the case: the intelligence is the same, and only the delivery speed changes. So the question is no longer "do I accept worse answers to go faster?" but simply "is the extra per-token cost worth the lower latency for this task?"
Who gets it
Per GitHub's changelog, fast mode is available on:
- Copilot Pro+
- Copilot Max
- Copilot Business
- Copilot Enterprise
On Business and Enterprise, an admin has to enable the fast-mode policy in Copilot settings before it shows up for developers. The rollout is gradual, so it may not appear in your model picker the moment you read this.
Pricing, honestly
Fast mode is priced at:
- $10 per million input tokens
- $50 per million output tokens
Anthropic says this fast mode is roughly 2.5× faster and about 3× cheaper than fast mode was for previous models. That is a meaningful improvement on the prior fast-mode economics. But read it carefully: fast mode still costs more per token than standard Claude Opus 4.8. It is a speed-for-cost trade, not a blanket discount - you pay a premium to shave latency.
When to use fast vs standard
Because the intelligence is identical, the decision is purely about latency versus cost:
- Use fast mode for interactive and agentic coding where waiting hurts - quick inline edits, tight feedback loops, and agent runs where output speed is the bottleneck.
- Use standard Opus 4.8 for non-latency-sensitive work - batch tasks, background generation, or anything where a few extra seconds do not matter - because it remains cheaper per token.
Agentic coding is where the speed difference is felt most. When an agent runs a multi-step task - reading files, planning, editing, then re-checking - each step waits on model output, and those waits compound across a session. Shaving latency at every step can turn a sluggish agent run into one that keeps pace with you. For one-shot questions or background jobs, that benefit largely disappears, and the cheaper standard model is the sensible default.
If you are weighing Copilot against other tools entirely, see Cursor vs GitHub Copilot and our GitHub Copilot alternatives roundup.
How to enable it
- Make sure you are on a supported plan (Pro+, Max, Business, or Enterprise).
- On Business or Enterprise, have an admin enable the fast-mode policy in Copilot settings.
- Open the Copilot model picker and select Claude Opus 4.8 fast mode.
- If you do not see it yet, that is expected - the rollout is gradual.
The bottom line
Claude Opus 4.8 fast mode gives GitHub Copilot users on paid tiers the same Opus 4.8 quality at much higher speed, at $10/M input and $50/M output - roughly 2.5× faster and ~3× cheaper than the previous fast mode, though still pricier per token than standard Opus 4.8. Reach for it when latency is the constraint; stick with standard when cost per token matters more than speed.
If you are comparing agent-style tools and terminal workflows alongside Copilot, read Cursor vs Claude Code and our best AI coding assistants 2026 overview.
