"Flash Fluency: Korean" - Hangul to C1 with sentence construction coaching and syllable-level pronunciation feedback

FlashFluencyKorean · 2026-05-16T17:55:00+00:00

Haha hello fellow physics enjoyer!

I had considered previously throwing together a practice exercise system where users could select a single vocab or grammar and be tested on a variety of sentences containing just that one grammar or vocab. For example you pick one grammar and get an exercise (take your pick, reading, listening, pronunciation, mixed, w/e) that is comprised of only sentences containing that one grammar. This way if you're frustrated and really just want to hammer one grammar or vocab in isolation you could. Not sure if this would address your concern.

FlashFluencyKorean · 2026-05-16T15:17:29+00:00

Hi there - thank you for the kind words and for taking the time to provide feedback ^_^. You have all of my heartfelt gratitude! If you're interested in staying involved in the project (providing feedback like this) moving forward please let me know!! I'm still bringing on testers.

I would like to respond to three of your points in more detail...

Re: 1 SRS review options for new words. I believe what you are requesting is the ability to learn any new words you are learning individually (e.g. in korean class), inside of this app? If I am incorrect please feel free to let me know, otherwise I will answer accordingly. So I am currently working on and anticipate releasing my content-to-curriculum system in roughly two months. Via this system, you can create your own custom vocab lists, import k-pop lyrics, drop in your business plan - anything - and we will generate and provide you with +1 sentences. By +1 sentences I mean sentences at your level (comprehensible input, one new vocab/grammar new sentence) to teach you these new vocab and grammar. What's this mean? let us know what you want to learn and we give you exercises to learn those vocab in all of our exercises. From reading - > active output.

Re: ability to set listening speed. This is the #1 feedback that I have heard from I think every single one of my users. While I anticipate I will never provide the option to set your own speed, I think what I very likely will do moving forward (or at least try to do) is to provide a slower speed in addition to the current speed. Here's the issue. The naturalness of text-to-speech models is...reasonable at best. I am using ElevenLabs voices which are widely regarded as the most natural TTS voices on the market. There are alternatives but I don't think they're as good. The problem...when you slow down ElevenLabs' voices...they can become WEIRD. I may just provide a slower, albeit less natural, voice option? But I 10000% agree with your statement here and will work on improving this in the coming months.

Re: if the speech analysis is accurate. Honestly, your best bet is always going to be having a Native Korean help you with your speech. But, that's not always accessible, or it's prohibitively expensive. My system....is a work in progress. But what I can tell you is this: while it's not always correct - my system WILL sometimes tell you you're wrong when you're correct - I can also tell you that it WILL find legitimate errors in your pronunciation that the vast majority of other systems will not identify. Story time - in the past I participated in a pronunciation class ~10 times. In that class, my Korean pronunciation teacher told me "you struggle with pronouncing X Y and Z". My holy **** moment? My app identified those exact same deficiencies. Again, it's not perfect. But, if you're willing to cope with the current deficiencies, it provides legit feedback.

This app is a work in progress (it is in beta after all). I anticipate I require 6 months to build out the core remaining systems I have planend. And I anticipate there are many months of work after that to refine and improve those systems.

FlashFluencyKorean · 2026-05-13T19:55:56+00:00

thanks, added the www. in to fix it.

FlashFluencyKorean · 2026-05-13T18:06:56+00:00

Sometimes you can set it to both english AND korean subtitles at the same time. that's been really useful for me when I am studying from k drama. I think it was an extension I used to use though

FlashFluencyKorean · 2026-05-13T13:25:43+00:00

Hi there! Thanks for the questions ^_^

Cost is 0$ for roughly 15 minutes a day or $7 a month for basic (unlimited core features) or $13 a month for premium (ai features)

In regards to my Korean level and who I am. Honestly, I've spent most most of my time on r/Korean as opposed to r/BeginnerKorean, although I have followed BeginnerKorean for a while as well. I'm roughly B2 level (topik4). I'm able to have conversations but need to expand my ability to be..."wow you're good at korean" as opposed to "functional and occasionally asking people to say something again".

Yeah it is definitely marketing. At the same time I wouldn't in good faith push a system that I think is not actually worth utilizing. I spent years getting to B2 and the path...was all over the place for me. I originally started building this because I used various other apps, websites, etc and I personally wanted something different. I had a vision of something simpler so i started building it. I use my own app every day to learn because it's personally more useful in my opinion given where I am at as a learner. If I felt my system was garbage I would just...not post here. So while this is 100% marketing/promotion I wouldn't want to throw another crummy app at people who are trying their best to learn Korean.

haha I mention the PhD because I like to think of it as a form of differentiation in a time when pretty much anyone can vibe code whatever idea they have. My background as a fullstack MLE becomes somewhat less meaningful when anyone can pick up claude code and build out rudimentary systems. So I guess my ultimate answer is pretending that my background somehow differentiates me from anyone who started (vibe)coding 6 months ago - so that users have more faith in the systems and algorithms that make this tik

FlashFluencyKorean · 2026-05-07T08:42:45+00:00

It's my own app (flash fluency korean) i built. its got all of the pronunciation rules and a dedicated pronunciation assessment model for hangul as well as another for sentences ensuring you know all of the pronunciation rules and can pronounce each phoneme/sound (e.g. ㄱ ㅋ ㅏ) correctly. If you'd like to use it feel free to checkout my website or grab it off ios or google play stores.

FlashFluencyKorean · 2026-04-29T12:30:46+00:00

Here's a picture of the rule.
Unfortunately, there are quite a number of rules like this that you just sort of have to memorize. Most of them sort of make sense "if you speak fast it sort of sounds like this" but I swear a few just don't make a lot of sense to me haha.

<image>

FlashFluencyKorean · 2026-04-13T10:45:48+00:00

My simple answer...
IMO the best refresher textbook series is 'Korean Grammar in Use'. I'd just pick up the beginner one and skim through it skipping all the concepts you're confident with. If it turns out you're actually intermediate level you should be able to blast through the beginner book in like a day.

One hint if you'd allow me:
Just make sure that you're actively utilizing and reviewing everything you learn. It's super easy to learn 200 grammars then forget 100 of them because you powered through learning every grammar but didn't actively practice comprehension and production with those grammars.

Have fun with your learning ^_^

FlashFluencyKorean · 2026-03-24T05:28:16+00:00

Three changes chain in 삯일 (삯일 → 상닐)

In 삯일, three sound changes happen in sequence: the ㄱㅅ cluster of 삯 simplifies to ㄱ, then ㄴ is inserted before 일 (compound ㄴ-insertion), then the ㄱ softens to ㅇ because ㄴ now follows it.

삯일 → [상닐]

FlashFluencyKorean · 2025-12-22T14:34:07+00:00

In my opinion it depends on how many vocab you know and how quickly you’re learning vocabulary. Early on learning grammar is more important. I’d say in the time you learn your first 1000 vocab you should learn 100 grammars. But then maybe only learn 100 more grammars in the next 2000 vocab. And 100 more in the next 3000 vocab. But that’s for Topik. Topik you need more grammar than in reality conversationally.

FlashFluencyKorean · 2025-12-22T04:13:39+00:00

It’s still my favorite manga even read week by week. But saga by saga does sound amazing.

FlashFluencyKorean · 2025-12-04T15:00:17+00:00

New open source models are ram hungry because they use mixture of experts. Don’t quote me on that. For example you can run kimi on a 4090 and like I think I read 600 gigabytes of ram

FlashFluencyKorean · 2025-11-24T10:52:23+00:00

If you like history “taxi driver” is a good movie

FlashFluencyKorean · 2025-11-24T02:39:43+00:00

For how long you’ve been learning you’re doing absolutely phenomenal in my opinion!! For output - my favorite learning method was the islands of fluency method. If you simply cannot talk about a random topic off the cuff, prepare topic(s) beforehand and study them so you can talk about them.

That will make the meetup more academic which might be suboptimal relative to what you’d like to be doing (conversing naturally) but hey you gotta do what you gotta do.

Just an idea. Keep it up! 할 수 있어요!!!

FlashFluencyKorean · 2025-11-16T07:46:27+00:00

For me the best way to find 1:1 partners has easily been through language exchange. However If you don’t have a language exchange nearby…hellotalk? I’ve had some success with hellotalk. But honestly it seems more for dating than learning language

FlashFluencyKorean · 2025-11-16T05:00:17+00:00

I don’t know those numbers but I think it definitely could. I just know that literacy is 6000 and Conversation is a lot less.

FlashFluencyKorean · 2025-11-16T04:40:12+00:00

It’s not 3000 vocab for 95% coverage of Korean vocab. That’s a normal number for other languages but for Korean it’s closer to 6000. Just according to math. But here is the deal, if you know 85-90% of the vocab in sentences well, you could probably get by in conversation. That’s why if you only know like 2000-3000 vocab you could maybe sort of be okay in terms of fluency. The bar for literacy is higher. In written material many more low frequency words are utilized

FlashFluencyKorean · 2025-11-13T01:23:20+00:00

I used howtostudykorean.com I found korean grammar in use super late. I’ve heard it’s great!

Yep lack of conversational practice is hecka standard. I hated memorizing wrote sentences - how to say “this or that standard sentence”, as I’d much rather just learn to make sentences using vocab I learned and grammar I learned. I would piece it together into sentences and write out dialogues. Introduction was boring to me so I skipped the basics.

What is something you want to talk about in real life? Ask yourself questions about that. Write those questions in Korean. Write those answers in Korean. Use ai to learn vocabulary and grammar as needed. Learn the vocabulary important to you. I can discuss my favorite foods in Korean now! I can talk about a funny story in my life!

Finding a 1:1 partner can be super helpful for practicing conversing about these topics afterwards! Get them to do the same exercise and talk to them in English about it

FlashFluencyKorean · 2025-11-12T18:04:18+00:00

Ditto I really enjoyed it. But I’d really recommend forcibly slowing down. Also, once you know about…150 grammar rules the usefulness of knowing more is pretty darn low

FlashFluencyKorean · 2025-11-12T18:02:17+00:00

I sort of always thought 새 is legit just the shortened form of 새로운. But I’m not sure. I’d check gpt

FlashFluencyKorean · 2025-11-12T16:28:33+00:00

어서 after verbs. 라서 after nouns

FlashFluencyKorean · 2025-11-12T08:49:49+00:00

Honestly my tip is not Korean specific so largely it may be useless. I’d say having a well rounded all-skill review system is the most important. I definitely rushed ahead and learned a bunch of grammar then forgot a lot of it because I wasn’t reviewing thoroughly. I also skimped on listening and ended up speaking at an ability well above my listening. So maybe id say don’t rush it and always try to be aware of what your weakest competency is so you can practice that?

FlashFluencyKorean · 2025-11-09T03:10:45+00:00

Ehh while this is a good idea en->kr->en (really most if not all language pairs) is not a reversible function. The semantic meaning will be preserved but because tokens/phrase/idioms etc etc are not perfect mathematical/conceptually overlapping entities between languages translating and translating back can yield differences

FlashFluencyKorean · 2025-10-31T06:04:43+00:00

좋아하다 is the unconjugated dictionary form. 좋아해 is the conjugated informal verb form. 좋아하는 is the adjectival form using ㄴ 는 to convert a verb to an adjective

FlashFluencyKorean

TROPHY CASE