How hard it is to reach 1400+ blitz

I started playing in December(15th) 2020 and reached 1400 in March (2021), its not that hard, learn one opening for white and one opening for black, do puzzles, look for tactics and dont hang free pieces, you should be able to reach it easily.

Just focus on undefended pieces, that alone should help you to reach 1200 in blitz.

1400 is a serious rating, which means they have put the effort in to improve, but they still have many errors. They still blunder like crazy. 

I would advise you to watch John Bartholomew's videos, specifically the "Climbing the Rating Ladder series"... in your case, its the first video, for players under 1000. That's what I did, and now I play around mostly in the 1500-1600s

If you work hard, it shouldnt take you more than a year, if not less depending on how much you play

Good luck

(I shortened my quotation so it isn't so long)

I went years without an upgraded chess.com membership - I reached 1500+ (probably 1600 or 1700 too) without ever upgrading membership. In fact, I currently have a gold membership because it was generously gifted to me

chess.com membership upgrade is nice to have if you use it, but it isn't required to get better. In fact, opening principles and basic theoretical endgames are easy to Google or search YouTube about. 

As for tactics/chess puzzles, I routinely did my "free" 5 puzzles per day on chess.com and the "daily puzzle" - that worked well for me

Similarly, you also get one free puzzle rush attempt per day - you could even use puzzle rush survival if you really wanted exposure to puzzles (survival mode didn't exist when I joined chess.com though).

I am just copying what I posted in another similar topic but I made some adjustsmentes, hopefully it might help....

Play longer time formats.... 10 minutes or even 15|10... maybe even longer if you have the time. That doesn't mean you shouldn't play blitz, but even you play longer time formats you'll have more time to look at your moves and understand what's going on. With practice  you'll see things quicker and play blitz better. When you play blitz try 5 minutes before trying 3. There's no such thing as too old for blitz. Maybe when it comes to dirty flagging, but don't worry about that....

Study the opening principles. Develop, control the center, castling to get your king to safety, etc. Don't waste too much time memorizing openings. Pick one with white and stick to it: I recommend 1.e4 as white (Ruy Lopes or italian) and as black maybe a response to e4 and d4, but don't spend too much time on it and especially don't memorize it. It's honestly a waste of your time memorizing. Just try to learn and understand the principles I mentioned early

Make sure you know how to perform basic checkmates.

King and two rooks (or King and 2 queens - or King rook and queen) - they are very similar

King and Queen

King and Rook

If you don't know how to do that, there's not much point in learning everything else and playing well during the whole game and then when it's time to win you don't know how... these are a must!

Checkmating patterns will do you wonders as well. Also look for ways of trading down pieces when you have a material advantage so you can take the game into a winning endgame and convert it into a victory. Also avoid trading when you're down in material.

Analizing your games (especially the ones you lost) will help you a long way, but not much if you're memorizing. Having a more experienced player go through your games with you would be best if possible. Also, don't just play and do puzzles, study. There are plenty of helpful content here on chess.com and youtube. Maybe check out agadmator's channel on youtube if you feel like it...then pay attention to how masters think and plays. He covers classic chess games as well as contemporary games and gives some tips for beginners. There are also other channels with educational material for beginners, I would recommend John Bartholomew... The learning content here on chess.com is good as well

Lastly but not least, do some puzzles and especially stop hanging pieces. 

If you learn opening principles, do some puzzles/tactics, basic checkmate patterns, and most importantly stop hanging pieces, then learn how to trade down when you have material advantage you can relatively easily get to at least 1200 elo rather quickly...  but always one step at a time.

Most importantly, keep making sure you're having fun, as that is the best way to get good at something. Good Luck

Not for me lol

Woah some people said it only took a few years. 

For me I think blitz is hard too, but it is fun.

Arhhhhh you gave chess so much commitment, my biggest mistake is blindly playing.

I do van't krujis openings 

yes Blitz is fun and the being too old comment was not about 1 off games but tournaments where you play 7 games. My brain can't cope by the 6th and 7th games

For me I really hate bullet, I don't mind blitz. But rapid is also hard for me lol

Will be moving on to Rapids as soon as Blitz hits 1000 games. It is Rapid I really wanna improve on

900 blitz rating = beginner who just started a few months ago, knows the rules but struggles with basic strategic concepts like developing properly or spotting pins and forks.

1400 blitz rating = intermediate club level chess player, knows a few openings fairly well, can spot basic tactics fairly consistently, knows basic endgames like opposition.

To go from beginner to an intermediate club level chess player, you will usually need to play and study fairly consistently (at least 5hrs per week) for at least 1-2 years. You'll have to take chess somewhat seriously to reach this level.

I can’t tell how hard it is....but a few tips will definitely enhance your skills (I’m not a pro so to give you tips but these are the tips I use to follow and is given by a lot of talented players like @llama, etc.)

first, try not to lose any piece for free....sometimes it might seem like “okay we’ll see that later” but it can cause trouble. Even a single pawn profit is a big thing. 
second, use longer time controls...and play as much as you can regardless of ratings. This way you can understand patterns that your opponent commonly used against you. 
third, play only a single type of opening all the time until you recognize every possible defense moves against your opening....I have seen people talking about caro, kann, Sicilian, etc. but non of them were expert at any of these... 

fourth, dedication and determination...which I believe you’ve already

there are more like...The CCT i.e. to look for Counter, Capture and Threat in every game. I’ll post more if I try them myself and if the are worthy.

It took me about 3 month to get from 900 - 1400 blitz. However I played a lot of chess, about 3 hours evrry weekday and 7 hours every weekend

By playing only blitz it would be difficult yes

lol some have given it way more commitment than I have Really, I've got many other hobbies in life, I'm a university student and I'm even a chess writer. It isn't just how much time and commitment someone has, but also how they efficiently utilize their time. Before you know it, several years have sneaked up on you and you are typing long paragraphs of advice to others on chess.com forum threads

p.s. part of my early determination was greatly fueled by a chess friend of mine who was "GM-like" in ability through my eyes - just hearing them play and go over games from memory, I could tell how much knowledge of chess they had. After literally years of working on my chess to finally win against them, I did it and surpassed them. In retrospect, that "GM-like" ability was closer to 1700, but I didn't even know ratings existed before I joined chess.com

Well, at 1700 you’d have a sound understanding of the game and you usually (should be) confident in your own analysis. 

I´m 47 years old and it took me 2 months to reach 1400 in blitz. When i was a kid i was "a math genius" and people wanted me to play chess but thought it was boring. Now at older age i have interested about it and find out that my fast brain works really well with blitz game format. Maybe i should taken chess more seriously as younger age. Now its too late to become pro player.

Define "pro" xD Chess World Champion, or Grandmaster (GM) is unlikely. However, just becoming titled (IM, NM, CM etc.) is still possible if you are willing to invest the time and effort to improve (but this "if" most don't find worth it). 

Mikhail Tal reached his peak 2700+ rating at age 44!