AI chat

Every frontier model. One conversation.

Research, write, analyze and code in one continuous conversation. Ask once, then switch assistants mid-thread to compare answers without losing context.

Free credits on signup · no card required · see pricing

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One creative workspace

Less switching. More making.

Use AI chat to research, write, analyze, code and compare answers in one conversation. Switch assistants without losing context and start chatting free.

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GPT, Claude, Gemini, Grok, Perplexity and DeepSeek behind one login

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Switch models mid-conversation without losing the thread

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Perplexity Sonar for questions that need live sources, not recall

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One credit balance instead of five separate subscriptions

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Six frontier chat models, one subscription

Paying for ChatGPT, Claude, Gemini and Perplexity separately means four subscriptions, four histories, and four places to check. Unify puts them behind one login and one credit balance. GPT is the strongest generalist for reasoning and code. Claude handles long documents and careful writing with the most consistent tone. Gemini is fast and strong on multimodal input. Grok is direct and current. Perplexity Sonar searches the live web and cites what it used. DeepSeek is a capable low-cost option for bulk work. You are not locked into whichever one you happened to subscribe to first.

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Switch models mid-conversation

The most useful thing about having every model in one place is that you do not have to choose upfront. Start a thread with a fast model while you are still shaping the question, then switch to a stronger one when the problem gets hard, without re-pasting context. When an answer looks confident but you are unsure, put the identical question to a second model and compare. Disagreement between two models is a reliable signal that the question is harder than it looks, or that the answer depends on something you have not specified.

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Which model for which question

Use a search-grounded model — Perplexity Sonar — whenever the answer depends on something that changed recently, because a model answering from training data will sound equally confident whether or not it knows. For code, GPT and Claude are both strong, and Grok Code Fast is worth trying when you want speed over depth. For long documents, summarisation, and anything where tone matters, Claude tends to hold structure best across thousands of words. For quick factual lookups and multimodal input, Gemini is fast and inexpensive. When cost is the constraint and the task is routine, DeepSeek does most of it for a fraction of the credits.

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Getting better answers

The quality of an answer is mostly set by the question. State the decision you are trying to make, not just the topic. Supply the constraints — audience, budget, timeline, what you have already ruled out — because a model cannot infer them and will otherwise give you the generic answer. Specify the output format you want. Then ask the model to state its assumptions and flag anything it is unsure about, which turns a confident-sounding paragraph into something you can actually check. For consequential questions, ask a second model the same thing before you act.

Prompt starters

Start specific. Then make it yours.

Technical comparison

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Compare two approaches for [problem]. Give the trade-offs on performance, cost, and operational complexity, state your assumptions, and recommend one for a team of five.

Research with sources

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What changed in [topic] over the last six months? Cite primary sources for each claim, note anything disputed, and flag what you could not verify.

Good to know

Clear limits. Better decisions.

  • Models differ on recency: ask a search-grounded model when the answer depends on current facts.
  • Any consequential answer should be verified against a primary source, whichever model produced it.

Frequently asked questions

Which AI chatbot is the best?

There is no single winner. GPT is the strongest generalist, Claude is best for long documents and careful writing, Perplexity is best when the answer needs live sources, and Gemini is fastest for multimodal input. Unify gives you all of them so you can compare on your own questions.

Can I use AI chat for free?

Yes. New accounts include free credits with no card required, enough to hold real conversations across several models before choosing a plan.

Can I switch models in the middle of a conversation?

Yes. You can change model mid-thread without losing context, which makes it easy to start cheap and escalate to a stronger model only when the question needs it.

Which model can search the web?

Perplexity Sonar searches live and cites its sources. Use it whenever the answer depends on recent information rather than what a model memorised during training.

Ask your first question free

New accounts start with free credits and no card. Put the same question to two models and see which one actually answers it.

Start chatting