tok

Exact Claude token counter for the terminal. Reuses your local Claude Code login from the macOS Keychain — no ANTHROPIC_API_KEY required — and calls Anthropic's official count_tokens endpoint, so the number matches what Claude actually bills.

Build

cargo build --release
# binary at target/release/tok  (optionally: cp target/release/tok ~/.local/bin/)

Requires that Claude Code is installed and you've logged in at least once (claude). The OAuth token is read from the Keychain entry Claude Code-credentials.

Interactive mode (default)

Run with no input to open a Claude-Code-style field with a live count:

tok

• Type or paste your prompt — the token count and estimated input cost update as you edit (debounced).
• Ctrl+V — smart paste: attaches an image if the clipboard holds one, otherwise inserts text. (Plain ⌘V text paste also works.)
• Pasted images appear inline as [Image 1], [Image 2], … just like Claude Code. The placeholder is display-only — the image itself is counted as an image block, the [Image N] text is not.
• Ctrl+X — drop the last attached image · Ctrl+L — clear everything
• Esc / Ctrl+C — quit

Pipe / scripting mode

Any text, file, or image argument switches to a single count-and-print:

tok "Hello, world!"              # -> 16 tokens · ≈ $0.000240 input
echo "from a pipe" | tok          # reads stdin
tok -q "just the number"          # -> 11   (integer only, for scripts)
tok --file prompt.txt             # count a file's contents
tok "describe this" -i shot.png   # text + image (repeat -i for more)
tok -m claude-haiku-4-5 "hi"      # price reflects the chosen model

The cost shown is the input cost (what it takes to send this prompt once) at the model's per-token input price — count_tokens doesn't generate output, so there's no output cost to include. Prices are approximate, matched by model family (opus/sonnet/haiku).

Options

flag	meaning
-f, --file <PATH>	read prompt text from a file
-i, --image <PATH>	attach an image (png/jpg/gif/webp), repeatable
-m, --model <ID>	model to count against (counts are identical across Claude models)
-q, --quiet	print only the integer
--interactive	force the field even when input is piped

How it works

tok reads the claudeAiOauth.accessToken (scope user:inference) from the Keychain and POSTs your text/images to https://api.anthropic.com/v1/messages/count_tokens with the anthropic-beta: oauth-2025-04-20 header. It only sends content for counting; no completion is generated and nothing is billed for tokens.

If you see a 401, your login expired — run claude once to refresh it.