How to Use a Vacuum Sealer: A Beginner’s Step-by-Step Guide

How does a vacuum sealer work?

A countertop (external) vacuum sealer has a pump, a vacuum channel with foam or rubber gaskets, and a heated seal bar. When you close the lid on the open end of a bag, the gaskets create an airtight chamber around the bag mouth. The pump draws air out through the textured channels in the bag, and once the vacuum is reached, the heated bar melts the bag’s layers together to seal it. Chamber sealers work differently — they evacuate the whole bag inside a chamber.

Before you start

• Read your machine’s manual — controls and cool-down times vary.
• Use bags made for vacuum sealing. External sealers need embossed bags. See the bags buying guide.
• Make sure the drip tray is in place and the gaskets are clean.

Step 1: Make a bag from a roll

1. Pull out enough roll for the food, plus its thickness, plus about 3 inches of headspace. Our bag size calculator works this out for you.
2. Cut straight across with the built-in cutter or scissors.
3. Place one cut end across the seal bar, close the lid and press Seal only. You now have a bag with a sealed bottom.

Step 2: Fill the bag

• Fold the top of the bag outward like a cuff while filling to keep the sealing area clean.
• Lay food in a flat, single layer where possible.
• Pre-freeze juicy, soft or liquid foods first. See sealing liquids.
• Pad sharp bones with a folded paper towel.

Step 3: Vacuum and seal

1. Wipe the inside of the bag opening if it’s damp or greasy.
2. Lay the open end flat inside the vacuum channel or drip tray — not over the seal bar only — with no wrinkles.
3. Close and latch the lid.
4. Select Dry for dry foods or Moist for damp foods (if available).
5. Press Vacuum & Seal. The machine will remove air, then seal automatically.
6. Wait for the indicator to finish before opening the lid.

Step 4: Check the seal

A good seal is a smooth, clear, even line across the full width of the bag, with no wrinkles, gaps or cloudy patches. If you’re unsure, seal again just above the first line — or use the double-seal setting if your machine has one.

Using pulse mode

For bread, berries, chips, delicate fish and soft cheese, hold or press Pulse to control the vacuum manually, then press Seal as soon as the bag is snug but before the food is crushed.

Using the accessory port

Many sealers have an accessory port and hose for canisters, jar sealers and zipper bags. Attach the hose, place the canister lid or jar adapter, and start the vacuum (often called “Canister” or “Accessory” mode). This is ideal for coffee, crackers and pantry goods.

Cleaning up

• Unplug the machine and let the seal bar cool.
• Remove and wash the drip tray if it’s removable.
• Wipe the gaskets and channel with a damp cloth and let them dry fully before closing the lid.
• Store with the lid unlatched so the gaskets don’t stay compressed.

See how to clean sealing strips and gaskets for more detail.

Common beginner mistakes

• Overfilling the bag so there’s not enough headspace.
• Getting moisture or grease in the seal area.
• Wrinkles across the seal bar.
• Sealing bag after bag without the cool-down your manual recommends.
• Using smooth bags in an external sealer.

Problems? Read Why Is My Vacuum Sealer Not Sealing?

Which sealer is easiest for beginners?

Look for simple one-touch controls, a dry/moist setting and an easy-lock lid. Our beginner pick is below; see all our best vacuum sealers.

Frequently asked questions