Skip to content

Incoming mail needs fields extracted for automation, regex or AI?

For mails with fixed templates (confirmations, invoice notifications) regex or an email parser is faster, more predictable and cheaper. For free text (customer mails) an LLM is better, provided you force JSON output.

Try this first

  1. 1Fixed template (Booking.com, bank notifications, supplier confirmations): use Mailparser, Parseur, or a Zapier email parser. Map once, low maintenance after.
  2. 2Free text, but predictable fields (name, question, urgency): use an LLM (Claude, GPT) with a JSON schema and a short example prompt. Keep temperature low.
  3. 3Combine where it makes sense: regex for headers (sender, date), LLM for body. That keeps cost lower than running every mail through an LLM.
  4. 4Always validate LLM output: try JSON.parse and fall back to a fallback flow if parsing fails. Don't push through blindly.
  5. 5Cost math: 1000 mails per month x 1k tokens x model price. At large volumes, a custom regex or trained classifier eventually pays off.

When to bring us in

Unsure if your volume justifies LLM or a regex, we can test both side by side on a week of mail.

See also

None of the above fits?

Describe your situation below. We pass your input plus the steps you already saw to our AI and return tailored next-step advice. If it's too risky to DIY, we'll say so.

Who are you?

For the AI question we need your email and company, so we can follow up if the AI gets stuck, and to prevent abuse.

Limited to 2 questions per hour and 5 per day, kept lean so the AI stays useful. For more, contacting us directly works better for you and us.

Or skip the DIY entirely

Our Managed IT clients do not look these things up. One point of contact, a fixed monthly price, resolved within working hours.