Compiler Explorer
Hacker ApprovedOnline compiler in Developer tools
Free website that shows the assembly a compiler produces from code snippets, so people can check optimizations and learn.
20 people recommended Compiler Explorer in Hacker News comments, 2 had mixed feelings and 1 criticized it, November 2025 to October 2026.
Summary written by Claude from 22 comments. It was written before the November 2026 recount, and 21 of those comments still count.
23 people gave an opinion
- recommend it
- 20
- mixed feelings
- 2
- warn against or regret it
- 1
The record
Recommended in 7 of 12 months
In 15 different threads.
- November 2025: recommended
- December 2025: recommended
- January 2026: recommended
- February 2026: not recommended
- March 2026: recommended
- April 2026: not recommended
- May 2026: recommended
- June 2026: not recommended
- July 2026: recommended
- August 2026: not recommended
- September 2026: not recommended
- October 2026: recommended
Why it carries the badge
- 20 people recommend itNeeds 10 or more, met.
- 20 recommenders for every criticNeeds 2 to 1 or better, met.
- Recommended in 7 of 12 monthsNeeds 4 or more, met.
- Recommended in 15 threadsNeeds 5 or more, met.
- The biggest thread supplies 15% of its recommendersNeeds half or less, met.
The same rules apply to every product, and the badge can’t be bought. Mixed feelings count toward neither side. How the badge works
What people say about it
Reasons grouped from a sample of 20 of the 24 opinions about it, picked in proportion to how many people recommend it, have mixed feelings and criticize it. Each mark is one comment in the sample. Open a reason to read what they said.
Why people recommend it
Each mark is one comment
Quick experiments with code snippets
“go to godbolt and load the rust aligned sum and play around with types”
Comment from 6 Nov 2025 in “The state of SIMD in Rust in 2025” “I normally start by typing a few lines of C into godbolt”
Comment from 25 Oct 2026 in “Small Programs and Languages” “can easily be solved by a minute or two on godbolt”
Comment from 20 May 2026 in “Everything in C is undefined behavior” - Comment from 7 May 2026 in “Nobody Reviews Compiler Output”
Checks compiled assembly and optimizations
“I always recommend people interested in optimization experiment running snippets of code through the compiler using godbolt with optimization turned on.”
Comment from 11 Jul 2026 in “Your code is fast – if you're lucky” “I think using Godbolt to disassemble things myself is the right approach.”
Comment from 11 Jul 2026 in “Your code is fast – if you're lucky” “You should always check the compiled assembly with Compiler Explorer”
Comment from 30 Oct 2026 in “Iterating Backwards in C” - Comment from 3 Dec 2025 in “You can't fool the optimizer”
Good for learning compilers
“Matt Godbolt's tool lets your reader play with your examples and learn more about what's going on.”
Comment from 20 Jan 2026 in “Understanding C++ Ownership System” “Feel like godbolt or an online compiler might be a reasonable starting place these days.”
Comment from 26 Mar 2026 in “The Little Book of C” “Godbolt taught me more than the compilers class itself”
Comment from 6 Dec 2025 in “ARM's Barrel Shifter Tricks” - Comment from 11 Jul 2026 in “Your code is fast – if you're lucky”
Works without local setup
“It lets you have that without the pain of hosting compilers server side.”
Comment from 1 Nov 2025 in “GHC now runs in the browser”
What people said
20 of the 24 opinions about it, picked in proportion to the three counts, newest first. Each links to the original comment.
“You should always check the compiled assembly with Compiler Explorer”
“I normally start by typing a few lines of C into godbolt”
“It doesn´t take being an expert to start to recognize the (auto) vectorized bits”
“Compiler Explorer is not good for measuring anything in general”
“I think using Godbolt to disassemble things myself is the right approach.”
“Godbolt.com is a fun way to learn”
“I always recommend people interested in optimization experiment running snippets of code through the compiler using godbolt with optimization turned on.”
“can easily be solved by a minute or two on godbolt”
“it is cool way to share code snippets”
“Feel like godbolt or an online compiler might be a reasonable starting place these days.”
“Matt Godbolt's tool lets your reader play with your examples and learn more about what's going on.”
“Godbolt taught me more than the compilers class itself”
“That's why compiler-explorer exists in the first place.”
“The nice thing about godbolt is that it can show you that clang”
“I used godbolt.org dozens of times, and I never bothered to look at "about”
“Between that and compiler explorer, it is fair to say he made the world a better place for many of us, developers.”
“You can never have too much Godbolt!”
“still am too addicted to using godbolt.org at this point”
“go to godbolt and load the rust aligned sum and play around with types”
“It lets you have that without the pain of hosting compilers server side.”
Counts come from 1,791,911 Hacker News comments labeled by Claude, November 2025 to October 2026, with data through October 31, 2026. Counts updated 2 Nov 2026. How we count. Report a mistake.