Free Browser Tool
Claude Prompt Caching Savings Calculator
Estimate daily savings from Claude prompt caching using current dated cache write and cache read prices from the Claude Platform pricing docs.
Without caching
$0
With caching
$0
Daily savings
$0
Savings rate
0%
Cost breakdown
How to use it
- Choose the model and cache TTL you expect to use.
- Enter cached prefix size, daily calls, cache rewrites, and hit rate.
- Compare uncached cost with cache write, cache hit, and miss costs.
- Use the result as a planning estimate, then verify with actual usage metrics.
Why this tool exists
Claude context work often fails because teams reason from rough vibes instead of a visible budget. This tool makes the tradeoff explicit while keeping all inputs local to your browser.
Treat the output as a planning estimate. For production routing, pair it with current Anthropic docs, real usage telemetry, and token counting against the exact model you call.
FAQ
Does prompt caching reduce context-window usage?
No. Cached tokens still count as context for the request. Caching reduces repeated processing cost and latency.
When does caching break even?
The pricing docs state that 5-minute caching pays off after one cache read and 1-hour caching after two cache reads.
Why is the Fable 5.1 cache read so much cheaper than its base input price?
Claude Fable 5.1 prices cache reads at 2.5 percent of base input rather than the usual 10 percent, which works out to $0.25 per million tokens. Anthropic described the change as a 75 percent cut at the September 1, 2026 launch, so a large stable prefix can be cheaper to re-read on Fable 5.1 than on a model with a lower base price.
Are the prices current?
The embedded prices were checked against Claude Platform pricing on September 19, 2026. Recheck before using them for billing commitments.
Sources Used
- Prompt caching, Claude Platform Docs. Accessed 2026-09-19. Official prompt-caching behavior, cache lifetime, prefix caching, usage fields, and invalidation patterns.
- Pricing, Claude Platform Docs. Accessed 2026-09-19. Official model pricing and prompt-caching multipliers for base input, cache writes, cache reads, and output tokens.
- Context windows, Claude Platform Docs. Accessed 2026-09-19. Official context-window behavior, token accumulation, extended thinking and tool-use accounting, and compaction guidance.