Best AI assistants

We run every assistant through the same fixed task set — summarisation, reasoning, code, retrieval and refusal behaviour — and record the outputs so the comparison is reproducible. Data handling is weighted equally with capability: what is retained, what trains the model, and what a business tier changes.

AI· 4 products

Best AI writing tools compared

Four assistants judged on output quality, data handling, pricing transparency and how easily you get your content out again.

9.0

Top pick

OpenAI Assistant Pro tier

$200 / month

• Identical task battery run across all providers
• Accuracy and hallucination rate on sourced questions
• Data retention and training-use policy by tier
• Real cost at consumer and team usage levels
• Latency and availability during peak periods
• Export, integration and vendor lock-in

1. 01

   Criteria before candidates

   We write down what would make a product the right pick — and how each criterion is measured — before we look at what is on sale.

2. 02

   Documented specifications only

   Anything we state about a product comes from our own testing or from the manufacturer's published documentation, linked on the page.

3. 03

   Real-world testing

   Where a category can be tested, we test it over weeks rather than an unboxing session, and we publish the conditions we tested under.

4. 04

   Pricing checked, not quoted

   We do not print a price we have not verified, and we do not treat an RRP as evidence of a discount.

5. 05

   Commercial relationships disclosed

   Affiliate links, if present, are labelled on the page. No partner can buy a placement, a rank or a verdict.

The full process is documented in our review methodology and testing process.