$9.95 per month. Check out the pricing page to see the pricing details. We also do institutional licensing, and you can contact George to work that out. Our institutional rates are much lower than our individual prices.

Skritter's main focus is the writing of characters. Also emphasized is knowledge of which characters comprise vocabulary words. While we're at it, we train the tones on those characters. Those three things are actively recalled and scheduled using spaced repetition principles.

Soon! We've done a lot of the work for this, and when we build the front-end, you'll be able to space repetitions of active-recall practice on character and word pinyins and definitions, too.

Most critically, Skritter won't give you spoken practice, using words in sentences. You can make up sentences as you practice and say them aloud, which we recommend, but Skritter can't do it for you. Neither does Skritter teach grammar. Chinese grammar is blessedly easy, in comparison to many languages, but you'll want to study it elsewhere. That said, we are looking at integrating example sentences that are auto-tuned to your level in the future, which will provide some extra grammar exposure. After that, we're looking to add full-blown sentence practice. Oh, yeah.

We think a focused tool is best. If you practice writing characters on your own, which is the hardest part of learning Chinese and takes the most time, then you should have a tool that is designed for it. Skritter will work with you as you study those other things by supporting the vocabulary necessary to do them.

Yes! You can go to the Custom List Builder to give it a try. The UI isn't great, but it works. If you need help, feel free to contact us anytime. We're going to revamp the User's Guide shortly, so there will be a section in there describing how to do this shortly.

You bet. You can learn simplified, traditional, or both. Go to your Vocabulary page to choose which style you would like to learn.

5300, currently, and we add more whenever a list includes a character that we don't have yet.

We do support Japanese and you can try it free until early 2010 while we tweak it and make sure everything works fine. Go to your vocabulary options page to set your language preference, and away you go!

Probably not, sorry.

They are planned, if not soon. Let us know what languages you'd like to see.

We have many features planned. If you have ideas, please, tell us!

See instructions here from Pinyin Joe.

There are many resources for this over at [chinese mac].

Not yet, as mobile devices don't support Flash. (Some have Flash Lite, which we haven't tested with Skritter, but which we think won't work). Eventually, we'll make a mobile interface that doesn't use Flash; that's going to be awesome. We're thinking mostly about an iPhone version, the thought of which has us drooling.

Sure can, and it should work even better than the mouse, for which our handwriting recognition algorithms are designed. Make sure to install the drivers, though, or you may see relative mouse scrolling behavior instead of nice, absolutely positioned writing. On Windows, you might want to turn off pen flicks or press-and-hold for right click. Also, enable pressure sensitivity by checking "Use Wacom plugin" on the practice page settings--it will make your drawing look cooler.

Sure. Some people even prefer their touchpad. We find it harder and slower to write with many touchpads, but with practice it's still pretty good. A mouse will probably allow you to write faster, however.

Yes, for sure. We don't want to lock anyone in! We'll build a feature to export your characters and learning histories for personal reference or to plug into other SRSs. While that remains on the to-do list, if you really need your learning data now, let us know and we'll hook you up.

Green is correct. Things start green because if you skip them, it's as if you knew them--skipping things you know well is a good shortcut. Wrong answers for words you haven't yet gotten right are light red; if you had previously gotten it and now forgotten, it's red. Yellow is so-so and blue is too easy.

We'll do you one better. We're planning to improve tracking of AFKness, so the timer will stop counting sooner when you're not actually practicing. Right now, it stops counting after 30 seconds for characters, and 15 seconds for tones. Eventually, it will take mouse movement, window focus, etc., into account, and it shouldn't be necessary to manage the time tracking manually. At that point, you'll also be able to temporarily stop the clock by clicking on it.

If you took a quiz on everything you've added to Skritter, your retention rate would be your score, with 95% being a good target. Currently, it also weights characters, tones, words, etc., equally, although that may be a source of error if you're better at one than another. SuperMemo has some more information about it on this page, and we've some more in our blog comments.

Most fixes should end up on our blog; you can subscribe to the blog, or just check it every once in a while.

This can happen when prolonged connectivity issues prevent your practice of the character from being recorded (or you navigate away too soon after practicing it), so the Kitten thinks you still need to practice it.

The audio set we have (donated generously by ChinesePod) doesn't have most neutral tones, which are hard to do in isolation, or erhua. We are planning to add the missing neutral tones in the future.

We're still in the process of improving the recognition, so please let us know which strokes are giving you trouble. Some of the double strokes (like in 阝) are easier written as two single strokes, for now. It can help to make sure you write strokes with sharp corners, to help out the segmentation algorithm.

Right, Skritter isn't exceedingly accurate at this yet, so be prepared for these two messages when they don't make sense. They'll improve with more tuning on the recognition in general.

This may be related to other tabs open in your browser. Gmail especially can be brutal, or other Flash apps. Let us know what you're running and we can try to tune for performance.

It might be a loading problem due to lag. This bug has still had a few sightings after we rewrote all this code and is proving really tough to track down. Please, let us know if you see it and under what circumstances.

Alas! Please, tell us what's wrong, what browser you're using, and on what platform. We test on Firefox 2 and 3, Chrome, IE 6, 7, and 8, Safari, Epiphany and Opera, but we often don't catch bugs. IE 6 is given a simplified version of our site until we have the time to handle its non-standards-compliant behaviour. If you are using IE6, please consider upgrading.

Please, let us know which platform (Windows, Mac, Linux, etc.) you're on, which browser you're using, and what version it is. They should be working on most browsers and operating systems.

Since there can only be so many components to this software called "Recognizer" or "Stroke", and since we're such large dorks, you may hear us talking about crazy things, like how our Burritos are swarming on the Squigs or how the Kitten is fattening up nicely and is almost ready to open its eyes. Be not confused, for this is not madness.

Skritter is the program itself! Also, the small, furry guy you see in our logo is a Skritter.

When you write a stroke into Skritter, before your raw input is recognized and matched to a stroke in a character, it is a Squig. We collect Squigs to improve our handwriting recognition algorithms.

The Kitten is the intelligent system that prompts you with characters at scheduled intervals and adds new characters for you to learn. Our baby Kitten is enthusiastic, but dumb; as it learns from playing with users, it will become a wise teacher, yes.

To tune our handwriting recognition algorithms, we're using a modification of Particle Swarm Optimization which we call Burrito Swarm Optimization. The Burritos swarm around collected Squigs, at each step improving their tastiness and purging the gross ones from their swarm.

The Chef is the tool we developed for constructing a stroke-level database of Chinese characters, so that we can do stroke-level recognition.

The Drudge is our tool for classifying user Squigs to feed to the Burrito swarm.

The Phantom is the dark grey shadow of the character that appears when you press S (to Show).

The Infant is the sound system. When you're prompted with a character, the Infant will pronounce it for your pronunciation reference.