browser extensions / AI tools

best token counter extensions — 2026.

counting tokens manually is a chore. context windows fill up silently. API costs add up fast. here is an honest comparison of how to track tokens in ChatGPT, Claude, Gemini and other AI assistants — live, in the browser.

last updated may 2026  ·  covers chrome · firefox · edge

why token counting matters

  • context limits are silent — when your conversation exceeds the model's context window, earlier messages are dropped without warning. you only notice when the AI forgets things.
  • API costs are per-token — if you use the API, every input and output token is billed. a counter running in the browser tells you before you send, not after the invoice.
  • prompt engineering needs feedback — compressing a system prompt from 2,000 tokens to 800 changes cost significantly. without a live counter, you are guessing.
  • AI assistants hide the number — ChatGPT, Claude, and Gemini web UIs do not show live token counts. you have to install something or copy-paste to an external tool.

one extension we make.

tokcount is a free browser extension that adds a live token counter to the AI assistants you already use. no account, no data collection, no cost.

no extension
copy → paste → count

copy your prompt, open a tokenizer tool, paste it in, read the number. repeat after every edit.

  • breaks your flow on every message
  • no real-time feedback while typing
  • external tools like tiktoken or OpenAI Tokenizer are standalone — not in your browser
  • does not track cumulative conversation context
  • works on any text, technically free
no install needed

feature comparison.

feature tokcount (free) paste-to-tokenizer ChatGPT built-in Claude built-in
live counter while typing ✓ yes ✗ no ✗ no ✗ no
works in the browser UI ✓ yes ✗ separate tab ~ API playground only ~ API console only
estimated API cost ✓ yes ~ manual calc ✗ no ✗ no
tracks conversation context ✓ yes ✗ single paste ✗ no ✗ no
ChatGPT support ✓ yes ✓ any text ✓ native ✗ no
Claude support ✓ yes ✓ any text ✗ no ✓ native
Gemini support ✓ yes ✓ any text ✗ no ✗ no
no account required ✓ yes ✓ yes ✗ ChatGPT login ✗ Anthropic login
available on Firefox ✓ yes ✓ any browser ✗ no extension ✗ no extension
available on Edge ✓ yes ✓ any browser ✗ no extension ✗ no extension
price free free free (ChatGPT account) free (Claude account)

verdict by use case.

AI power user

tokcount

you switch between ChatGPT, Claude and Gemini. one extension that works across all three saves the tab-switching and paste cycle every time you tweak a prompt.

API developer

tokcount + API console

tokcount gives a live estimate in the chat UI while you prototype. the API console gives exact post-call usage in production. use both.

occasional use / one-off

paste-to-tokenizer

if you only need to count tokens once or twice, the OpenAI Tokenizer or tiktoken playground is fine. no install needed for a quick check.

frequently asked questions.

install tokcount free — takes 10 seconds.

live token count + cost estimate in ChatGPT, Claude, Gemini and others. works offline. nothing sent anywhere.

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