The absolute easiest way to can tomatoes! This step-by-step photo tutorial will show you how to can tomatoes in no time. No peeling, no coring- just cut out the stem and dice them up. It’s super easy, plus if you grow your own tomatoes, it’s a big money saver too!
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I started canning diced tomatoes several years ago after having an “aha moment” one evening while preparing dinner. As I was opening a can of diced tomatoes that I needed for the recipe I was making, I suddenly wondered why in the world I never tried canning them myself. I mean how hard could it be?
I grew up helping my mom can tomato juice and tomato chunks. And every year since we’ve been married, I’ve canned tomato juice as well as things like salsa and marinara sauce, so I was quite familiar with the process of canning tomatoes.
I decided to give it a try and it worked like a charm! It was not only super simple, it has also saved me from needing to buy diced tomatoes from the store.
How do you can tomatoes? Let me help you learn the process!
Supplies for Canning Tomatoes
- Tomatoes, salt and bottled lemon juice
- Dishpan or containers to put the tomatoes in
- Knife (This one is my favorite for slicing tomatoes!)
- Cutting board (The groove on this one is awesome because it catches the juice, creating less mess.)
- Vidalia Chop Wizard (Not a necessity, but you can dice the tomatoes in about half the time if you use it.)
– This gadget is also awesome for dicing tomatoes, onions, and peppers for salsa and potatoes and carrots for soups. - Wide Funnel
- Damp cloth to wipe jar rims
- Water Bath Canner (or this Canning Rack may work depending on what size pot you already own)
- Canning jars with lids and rings
- Jar lifter
- Old towels or rags to set the hot jars on
How to Can Diced Tomatoes- a step-by-step tutorial
1. Wash tomatoes thoroughly.
Cut out the stem and any defects or blemishes.
Some people also peel the tomatoes, but I never do and we honestly have not noticed the peelings at all and I’m even funny about textures like that in food.
I figure, why bother with the extra step? Plus it’s a bit healthier too!
2. Cut up the tomatoes.
Slice tomatoes into about ½-inch thick slices, then dice them into whatever size you want. I love using the large dicing side of my Vidalia Chop Wizard for this!
3. Place diced tomatoes into a clean canning jar.
A funnel makes this super easy. Gently shake the jar to settle the tomatoes so that you can fill it completely.
The tomatoes should be packed tightly to produce enough juice. It won’t hurt if you press down on them a bit to get the jar packed full- in fact, this is probably going to be necessary.
The jar should be full to the base of the neck.
4. Add salt and bottled lemon juice.
For the salt, use ½ tsp. per pint and 1 tsp. per quart. You do not need to add salt when canning tomatoes, but I recommend it because I think it helps enhance the flavor.
For the lemon juice, use 1 Tbsp. per pint and 2 Tbsp. per quart.
Once the salt and lemon juice are added to the tomatoes, wipe the rim of each canning jar with a damp cloth to remove any tomato residue that may be there. (If there is even a slight bit of tomato juice on it, it may not allow it to seal properly.)
I updated the original post to include the instructions to add lemon juice after several readers commented and said that to be safe, you really should add it.
5. Prepare the canning lids. (This may be optional!)
Update: Some canning lid manufacturers now say that it’s not necessary to preheat the lids. So before doing this, check the instructions that came with the lids you are using.
Once you have 7 jars filled, place 7 metal canning lids in a small pan. Cover with water; bring to a boil.
When the water boils, use a fork or lid lifter to lift the jar lids out of the water and place them on the jars. Be careful not to burn yourself!
Secure each lid with a jar band/ring. (Heating the lids softens the rubber, allowing for a better seal.)
6. Place the filled jars of tomatoes in the canner.
Once jars are full and have the ring and lids on them, place them in the canner.
Then add hot water to the canner, enough to cover the jars by 1 to 2 inches. Cover the canner with a lid. Turn the burner to medium-high heat.
Once the water starts to boil, reduce the heat slightly and process for 45 minutes, making sure the water is boiling gently and steadily the whole time. (You may need to adjust the heat to keep the boil going nicely, but as long as it is boiling, you are fine.)
7. Remove the jars of canned tomatoes.
After processing the canned tomatoes for 45 minutes, turn the burner off.
Remove jars using a jar lifter- you may want to have a dishrag in your other hand to catch any hot water that drips from the jars as you remove them- and place on an old towel, blanket or another padded surface. (This is to protect your counter from the super hot jars.)
Allow at least a little bit of air space around each jar, making sure not to have jars close enough to touch. Do not move until the jars are completely cool.
Jars should seal as they cool and you will typically hear a snap or pinging sound as the vacuum seal is formed. The lids will be slightly concave when sealed.
To test the seal, once the jar has totally cooled you can lightly tap the center of the cooled jar lid. If it is firm and does not move, it should be sealed. If it pushes in, it didn’t seal properly. You can still use unsealed jars, just put them in the refrigerator and use them as soon as possible.
After the jars are completely cool, you can remove the rings. Jars should be wiped clean before storing them.
Enjoy!
HELPFUL TIP: 1 pint of canned diced tomatoes is equivalent to 1 (15 oz.) can of diced tomatoes.
Other canning recipes you might also enjoy:
How to Can Diced Tomatoes
Equipment
- Dishpan or containers to put the tomatoes in
- Knife
- Cutting board
- Vidalia Chop Wizard (Not a necessity, but you can dice the tomatoes in about half the time if you use it.)
- Wide Funnel
- Damp rag to wipe tops of jars
- Canner
- Canning jars with lids and rings
- Jar lifter
- Old towel, blanket or other padded surface to put hot jars on
Ingredients
- fresh tomatoes (approximately 2 3/4 lb. for 1 quart jar)
- salt (1 tsp. per quart or 1/2 tsp. per pint)
- bottled lemon juice (2 tbsp. per quart or 1 tbps. per pint)
Instructions
- Wash tomatoes thoroughly. Cut out the stem and any defects or blemishes. Some people also peel the tomatoes, but I never do and we honestly have not noticed the peelings at all- and I’m even funny about textures like that in food. I figure why bother with the extra step, plus it’s a bit healthier too!
- Slice tomatoes into about ½ inch thick slices, then dice them into whatever size you want. I love using the large dicing side of my Vidalia Chop Wizard for this!
- Place diced tomatoes into a clean canning jar- a funnel makes this super easy. Gently shake jar to settle tomatoes so that you can fill it completely. The tomatoes should be packed tightly in order to produce enough juice. It won't hurt if you press down on them a bit to get the jar packed full- in fact, this is probably going to be necessary. The jar should be full to the base of the neck.
- Add salt (½ tsp. per pint and 1 tsp. per quart) and bottled lemon juice (1 Tbsp. per pint and 2 Tbsp. per quart). Wipe rim of each jar with a damp cloth to remove any tomato residue that may be there. (If there is even a slight bit of tomato juice on it, it may not allow it to seal properly.)
- Update: Some canning lid manufacturers now say that it's not necessary to preheat the lids. So before doing this, check the instructions that came with the lids you are using. Once you have 7 jars filled, place 7 metal canning lids in a small pan. Cover with water; bring to a boil. Once the water boils, use a fork or lid lifter to lift the jar lids out of the water- be careful not to burn yourself!- and place them on the jars. Secure each lid with a jar band/ring. (Heating the lids softens the rubber, allowing for a better seal.)
- Place 7 jars in canner. Fill with enough hot water to cover the jars by 1 to 2 inches. Cover canner with a lid. Turn the burner on medium high heat. Once water starts to boil, reduce heat slightly and process for 45 minutes, making sure the water is boiling gently and steadily the whole time. (You may need to adjust heat to keep the boil going nicely, but really, as long as it is boiling, you are fine.)
- After processing for 45 minutes, turn the burner off. Remove jars using jar lifter- you may want to have a dishrag in your other hand to catch any hot water that drips from the jars as you remove them- and place on an old towel, blanket or another padded surface. (This is to protect your counter from the super hot jars.) Allow at least a little bit of air space around each jar, making sure not to have jars close enough to touch. Do not move until jars are completely cool.
- Jars should seal as they cool and you will typically hear a snap or pinging sound as the vacuum seal is formed. Lids will be slightly concave when sealed. To test the seal, once jar has totally cooled, lightly tap the center of the cooled jar lid. If it is firm and does not move, it should be sealed. If it pushes in, it didn’t seal properly. You can still use unsealed jars, just put them in the refrigerator and use them as soon as possible.
- After jars are completely cool, you can remove the rings. Jars should be wiped clean before storing them.
Lisa
I have airspace in my finished jars is this ok and if not how do I avoid this?
Lydia Beiler
By airspace, do you mean space between the top of the tomatoes and the canning lid or do you mean that there are tomatoes above the juice in the jars? Both are not a problem and happen to me sometimes too. If a lot of the tomatoes aren’t covered, then it may be wise to refrigerate them and use them before too long. If it is just a small amount of tomatoes above the juice, they may darken over time but that’s normal and okay- it’s just because of the air exposure. They are still fine to use as long as the jar is sealed.
If you don’t have much juice in your jars, generally the causes are either the jar being filled a little too full, the jar ring not being tightened quite enough (they should not be overly tight, but snug) or the temperature fluctuating too much when canning.
Hope that helps!
Christine Layte
What kind of tomatoes do you use?Are Roma’s good to use?
Lydia Beiler
Over the years, I’ve used pretty much any kind of tomato for this. Less juicy tomatoes are ideal though, making Roma a great choice.
Nancy Lalonde
Hi Lisa, I want to add Italian seasoning to mine…how much do you recommend?
Lydia Beiler
I have never added Italian seasoning to mine, so I really am not sure what to tell you.
Kimberly Moore
Is it the same processing time if you only have 3-4 jars?
Lydia Beiler
Yes!
Carol Forneris
Do you use canning salt?
Lydia Beiler
I just use regular table salt. You can use canning salt if you prefer though.
Barbara Burton
Hi. Thank you for posting this easy method. Do you mix the salt and lemon juice into the tomatoes, or do you just add to the top of the jar?
Lydia Beiler
Just add them in on top of the tomatoes. As it cans, they both will get dispersed throughout the jars.
Ben becher
I can’t wait to try this out soon, thank you for the recipe! So there is no heating of the diced tomatoes needed prior to putting them in the jars and canner?
Lydia Beiler
You are very welcome Ben! And no, you don’t need to heat the tomatoes before jarring them. I hope the canning goes well!
Gayle Adams
I have about 1 inch of liquid in the bottom of the wide mouth jars when they finished processing but the regular mouth jars have very little liquid. I did pack them!
Lydia Beiler
Strange that the two styles of jars have different results! Juicer tomato varieties tend to produce more liquid but I presume you used the same kind of tomatoes for both the wide and regular mouth jars, so I’m not sure why it resulted in different amounts.
Shirley Deeds
Thanks for adding the note about the salt being optional. I canned tomato sauce with just the lemon and have been searching for recipes for diced tomatoes. We’re planning on expanding our tomato production this season because we are close to running out of sauce and salsa. Plus, the only thing I’ve had to purchase this winter was canned diced tomatoes. I don’t cook with a lot of salt and didn’t want to add it if I didn’t have to, yet every recipe I’ve found has called for sauce and a couple have stated that it wasn’t safe to can without it. I did a little research and found out that it wasn’t mandatory, but so far, your site is the only place where I noticed it being listed as optional in the directions. 😉
Lydia Beiler
You are welcome, Shirley! And I love that you preserve so much food. That is amazing!
Jeffrey
How full do you fill the jars?
Lydia Beiler
Hey, Jeffrey, they should be filled to the base of the neck of the jar- as stated in step 3 of the recipe instructions.