For professionals who live in their inbox, both GPT-4.5 and Claude 3.7 can act as powerful email assistants, but they have slightly different advantages.
Productivity Enhancements
GPT-4.5 is explicitly touted for communication tasks — one of its highlighted applications is “streamlined communication”: drafting professional emails, managing follow-ups, and helping schedule meetings. Thanks to its improved natural language ability and “emotional intelligence,” GPT-4.5 produces emails that read polished and human-like, with nuanced tone control. Early users report that GPT-4.5’s writing “doesn’t read like AI output anymore”.
It can capture a desired tone (e.g. formal, friendly, persuasive) and generate emails that need minimal editing. For someone dealing with dozens of emails a day, GPT-4.5 can save time by drafting replies or summarizing long threads into key points with action items. Its creativity also helps in phrasing things diplomatically or finding alternative wording, which can be useful in sensitive communications.
Claude 3.7 is also a strong writing assistant, with Anthropic noting significant improvements in content generation and planning in this version. One of Claude’s killer features for email-heavy users is its context length. Claude 3.7 supports an extremely large context window (up to ~200K tokens in the latest version) for input + output.
This means you can feed entire email threads, long documents, or multiple attachments into Claude and get a coherent summary or a contextual response. For instance, a user could provide Claude with a lengthy email chain (tens of thousands of words) and ask for a summary or a drafted reply that references specific details from earlier in the thread – something GPT-4.5 might struggle with if it exceeds its context limit (GPT-4.5’s context is likely similar to GPT-4’s, in the tens of thousands of tokens at most).
Claude 3.7 “can produce responses up to 128,000 tokens long – 15 times longer than its predecessor”, allowing far more detail when needed . This ability to handle and remember long conversations makes Claude very adept at maintaining continuity in email threads, preventing it from forgetting earlier details or instructions (a common pain point with smaller-context models). In fact, some users have said “nothing can match Claude's continuity” for long, detailed discussions.
AI-Assisted Writing Quality
Both models excel at generating well-structured, grammatically correct text, but users note subtle differences in style. GPT-4.5 tends to be extremely fluent and “creative” in wording, often producing a variety of phrasings that sound natural. It also has a higher “EQ” (emotional intelligence) according to OpenAI – meaning it can adjust the tone and empathy in writing, which is useful for customer-facing emails or delicate communications.
Claude’s writing is typically very clear and polite (Anthropic trains it with a focus on helpfulness and harmlessness). In earlier versions, Claude sometimes had a more verbose or formal style, but with Claude 3.7 it has become more concise and “upgraded” in its content generation. One professor noted after Claude’s update that it was capable of more free-form, less stilted responses – “Claude unchained!”, as he put it, describing a more engaging, less overly cautious style. For everyday emails, both can produce solid drafts; GPT-4.5 might give a bit more flair or warmth in phrasing, whereas Claude might stick closer to a factual, to-the-point summary (unless prompted otherwise).
Privacy and Security Considerations: When using AI to compose emails (which often contain sensitive or personal information), privacy is crucial. OpenAI and Anthropic both state that they do not use API data to train their models by default, which is important for business users. OpenAI clarified in 2023 that API usage won’t be used for model improvement unless you opt-in, and it launched ChatGPT Enterprise with guarantees of data encryption and no data retention beyond 30 days. Anthropic similarly promises not to use client-provided data from Claude for training unless a user explicitly flags it for feedback (I want to opt out of my prompts being used for training ...). In other words, if you use Claude via the API or Claude Pro, your inputs/outputs won’t end up in Anthropic’s training sets (barring abuse reporting). For everyday users, Claude offers a free tier and paid plans in a chat interface (claude.ai), and Anthropic’s privacy policy suggests that even chats on their platform are not used to retrain models unless you choose to give feedback. OpenAI’s ChatGPT (for Plus/Pro users) gives the option to turn off chat history, which ensures those conversations aren’t used in training data.
However, one should note that GPT-4.5 is initially only available to ChatGPT “Pro” subscribers (and API), and presumably Pro users’ conversations might be used by OpenAI to refine the model since GPT-4.5 is a research preview. OpenAI has invited feedback on GPT-4.5 to decide if it provides unique value. For corporate or email use where confidentiality is paramount, using the API or enterprise solutions of either provider is the safer route. ChatGPT Enterprise and Claude Enterprise both offer SOC 2 compliance and stricter data privacy.
Another aspect of security is how the models handle sensitive content in prompts/emails. Anthropic has a strong focus on AI safety with its “Constitutional AI” approach, meaning Claude is trained to refuse or safely handle harmful or confidential requests. Claude might be slightly more conservative in responses – for example, if an email draft might accidentally include sensitive personal data or problematic language, Claude could sanitize or warn about it. GPT-4.5 also has OpenAI’s refined safety filters, and with its broader knowledge base it may incorporate more up-to-date policy adherence. In general, both models are considered enterprise-grade in security, but Anthropic explicitly markets Claude as “trained to be safe, honest, and harmless” for workplace tasks. For an email-heavy user, this means Claude is unlikely to produce inappropriate content or leak information from prior parts of the conversation.
GPT-4.5’s improvements in reducing hallucinations (it hallucinated significantly less than GPT-4 in tests) also add to trustworthiness – you don’t want your AI assistant making up facts in a business email.
Productivity Integrations
It’s worth noting where these models might be integrated for email workflows. GPT-4.5 can be accessed in ChatGPT’s interface or via API, and we’re seeing it used in products like Microsoft’s **Copilot for Outlook (Microsoft 365 Copilot uses GPT-4 to summarize and draft emails inside Outlook). As GPT-4.5 becomes available via API, similar integrations will use it for even better results. Claude, on the other hand, has partnerships too – for example, Claude is available in tools like Slack (Claude can be added to Slack to summarize channels or answer questions) and through providers like Quora’s Poe or AWS Bedrock for custom integrations. A savvy email user could connect Claude 3.7 to their email via an API script to, say, summarize unread messages every morning or draft replies based on bullet points. Thanks to Claude’s large context, it could summarize an entire day’s worth of email threads in one go.
GPT-4.5 can also do email summarization and drafting (and faster), but one may need to chunk very large volumes of text due to context limits. In practical terms, both models can dramatically enhance an email-heavy workflow – saving time on writing and reading – and both providers seem mindful of privacy (neither wants to scare away business users). The choice might come down to whether you need Claude’s long-document handling and step-by-step detail, or GPT-4.5’s more fluid writing style and integration in tools you already use.