Claude Opus 5 vs GPT-5.6 — two locked chats, same audit
The search is Claude vs ChatGPT. On Slowtest both consumer boxes often refuse the 1-paste hook. This page is how to run the same audit anyway — own-key if you have keys, worksheet if you do not.
Reach for this pair when you are picking a long write between Claude Opus 5 and GPT-5.6 / ChatGPT in the same sitting. Do not wait for a marketing chart. Paste the same ~1000-word audit, or stream both from the home page. Who follows Line 1 and the word band matters as much as who finishes first.
Slowtest measures Generation tok/s when it has a real window (own-key first-to-last, or 1-paste start/finish beacons). Full-turn tok/s is the whole job. Fidelity is Line 1 MODEL: plus 800–1200 words. No tok/s on this page is a Slowtest measurement — the Insights ledger stays blank until a receipt is pasted. Method: How we measure.
Typical Claude chat is Blocked on 1-paste. ChatGPT consumer is Unrated and often will not POST. That is Harness Restriction, not IQ and not “0 tok/s.” Own-key hits Anthropic and OpenAI from your browser; keys stay in localStorage. If you have only one key, clock that side and write the other down as worksheet or skipped. Do not invent the missing number.
| What you can actually clock | Claude Opus 5 | GPT-5.6 / ChatGPT |
|---|---|---|
| Own-key Generation | Anthropic stream from the browser | OpenAI-compatible stream from the browser |
| 1-paste / Harness | Blocked — often refuses the beacon | Unrated — consumer chat often will not POST |
| Full-turn | Whole Claude job: think, tools, queue, POST | Whole ChatGPT job: wait, tools, UI slack, POST |
| Fidelity | Same audit: Line 1 MODEL:, 800–1200 words |
Same audit: Line 1 MODEL:, 800–1200 words |
| Honest pair | Same hour, same audit, same clock. Do not mix own-key with a silent 1-paste and call it a head-to-head. | |
Three questions for this pair
Can I time Claude and ChatGPT in the same consumer chats?
You can paste the audit. You often cannot get a 1-paste Generation clock. Typical Claude chat is Blocked on Insights. ChatGPT consumer is Unrated and frequently refuses outbound scripts. Use own-key if you have Anthropic and OpenAI keys, or the keyboard worksheet if you do not. A silent listener is not 0 tok/s.
Own-key for both — is that a fair pair?
Yes, if you stream both in the same hour on the same ~1000-word audit and compare Generation to Generation. Full-turn still includes each product’s wait and tools. Label the keys and the hour. Do not mix a Claude own-key stream with a ChatGPT worksheet stopwatch and call it a head-to-head.
Does a blocked harness mean the model is slower?
No. Harness Restriction is willingness to run wired-up — not IQ and not decode speed. Claude often refuses the beacon and is still a model you can clock with own-key. Fidelity is Line 1 plus the 800–1200 word band. Speed with a miss is not a score. Details: How we measure.
Clock both with own-key, or time the visible words
Do not treat a refused beacon as a score. Run the same audit. Keep Generation and full-turn on separate lines.
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