What can I do against King's Gambit!

can anybody tell me what the best reply to e4 e5, and then f4 as black?

A computer will tell you taking the pawn and it probably is the strongest.

I play Bc5 stopping d4 and keeping the white king in the centre.

2. Ke7, bringing the king into the center, is the strongest reply and shows white what a true king's gambit looks like.

Oh, we aren't talking about suicide chess. Well then take the pawn and say thanks!

Probably not, how is a total stranger supposed to know what is the "best reply" for YOU? There are several good defenses vs KG which is one reason why IMs and GMs do not employ it very much compared to the Ruy Lopez for instance, it's too easy to equalize against with several different lines AND White runs a big risk here - this is a REAL gambit and if Black is a greedy SOB he may just never give White the pawn back if he knows what he's doing.

If you're greedy and don't mind defending grab the pawn and start learning some defense that's designed to hold on to the pawn come hell and high water, I think 3...g5 is one.

2...ef4 3.Nf3 d5 is the Modern Defense which seems to be safe and sound for Black, although you'll probably return the pawn in exchange for easy equality.

If you're a wuss and don't like accepting gambits take Scottrf's advise and start playing (and learning, hopefully) the KGD with 2...Bc5

If you like to counter-attack or offer gambits yourself you can try playing the Falkbeer Counter-Gambit 2...d5.

Start going thru the Game Explorer here to check out various ways of replying to the KG   GOOD LUCK!

The best way to refute a gambit is to accept it STEINITZ

Check out this article by Bobby Fischer. It's called "A Bust to the King's Gambit"

It's quite helpful.

The article was written shortly after Fischer lost a KGA to Spassky in 1960 - well over HALF A CENTURY AGO. So I'm not sure about it being "quite helpful" if you don't look up "Fischer's Defense" in something a tad bit more modern, like MCO-15 or ECO 4th edition; or else use a search engine to come up with some stuff written in say, this century and not the previous one.

Here's the game in quesion, fully annotated

http://www.chess.com/blog/NimzoRoy/spassky-slam-dunks-fischer?_domain=old_blog_host&_parent=old_frontend_blog_view

Little old, but still.

I usually test some players with 2...Nc6 and pray they will play 3.fxe5? Qh4+! :)

I'll have to try that in blitz, or maybe the slightly more standard way of declining with 2...Bc5 -- might score me more quick points than how I've been playing for 40 years: 2...exf4 3.Nf3 Be7

I can tell you disappointingly few players fall into it. :(

You could try Falkbeer's counter-gambit. 2. ... d5!! If he takes the king pawn, bring your queen out and have fun. If he takes the queen pawn, push the king-pawn forward.

You can also get away with accepting the gambit and pushing all of your king-side pawns as well (note: ALL of your king-side pawns--don't leave a single king-side pawn unpushed!!!).

Three years later I come back to my post. I usually play the Marshall Counter-gambit with 2...d5 now. Surprising how many players fall into 3.exd5 c6 4.dxc6 Nxc6 5.fxe5 Qh4+ and mates or loses h1 rook...

2... Bc5 is a solid response (accepting the gambit is theoretically stronger but you'd better know those lines very well). Then white should play 3. Nf3, but if they're inexperienced you've given them an opportunity to blunder with 3. exf5 or 3. e5, where Qh4+ will give you a crushing attack.

If you dislike playing vs Kings Gambit, play Sicilian instead of Symmetrical King's Pawn.

3.e5 is impossible.  Why do people do this constantly?

Yeah sorry about the chess dyslexia or whatever, the relevant blunders are 3. fxe5 and 3. f5. And here's a youtube video of it happening in John B's "Climbing the rating ladder" series.

https://youtu.be/JgYy2QYQ-O4?t=15m52s