ContextThe buyer or use case, the need, and constraints that materially change product fit.
Source-led fact check
Is There a Context Hint Character Limit?
The public OpenAI guidance reviewed here does not state a universal character limit. Write for clarity and focus—not an unverified number.
No universal public limit is documented in the sources below.
The frequently repeated 280-character figure does not appear in the current public OpenAI ad-group or bulk-upload documentation cited on this page. Your current Ads Manager field remains the operational check.
A better editing rule
Use the shortest version that preserves meaning.
A useful hint still explains a real need or situation. Shortening it until it becomes a keyword list makes it less informative, not more precise.
Repeated keywords, decorative persona detail, ad-copy slogans, and clauses that do not change relevance.
Different products, audiences, use cases, or intent stages that need different creative or destinations.
The split signal
Length is a problem when one hint contains several jobs.
If removing a clause changes the product, buyer, intent stage, creative promise, or landing page, the draft probably contains more than one ad-group theme. Split the structure instead of compressing everything into one sentence.
One coherent need can be detailed. Several different needs should not share a hint merely because they fit within a field.
Unsure whether a draft contains several themes? Use the ad-group structure guide.