Runtime varies by refill technology. Many scented-oil refills list up to about 60 days per refill on a low setting, mist-style refills commonly list up to about 45 days, and other technologies often list around 50 days on low. Total longevity scales with pack size (for example, two refills ≈ two times the per-refill runtime).
Most vanilla plug-in refills are designed for electric outlets (oil-warmers or plug-in diffusers). Some diffuser systems and cordless units use batteries or are rechargeable/cordless, but the majority of traditional plug-in refills are mains-powered.
Many plug-in systems offer adjustable intensity. Oil-based warmers commonly provide multiple heat or scent settings, mist devices often list low/medium/high mist frequencies, and some units include a Boost or similar high-output mode. Available controls vary by model, so check the product details for exact settings.
Total pack lifespan depends on per-refill runtime. Per-refill on low settings is commonly cited in the range of about 45 to 60 days; using those figures, a two-pack can total roughly 90–120 days and some five-pack options are described as totaling up to about 225–300 days. These totals are approximate and vary by product and usage settings.