Chess players spend a surprising amount of money on analysis. Some of it is well spent. A lot of it buys things that have been free for years. This article is an attempt to sort one from the other without pretending that free tools do everything.
Engine strength is a solved problem
The first thing to understand is that the engine itself is not a differentiator anymore. Stockfish is free software under the GPL, it has won the top computer chess competitions for years, and every serious analysis product uses it or something comparable. When a site advertises "powerful engine analysis," it is almost always describing Stockfish, sometimes at a fixed depth.
What varies between tools is everything around the engine:
- Depth and time. How long the engine thinks per move, and whether that runs on your machine or on a server.
- Import convenience. Whether your games arrive with one click from Chess.com or Lichess, or whether you paste PGN.
- Presentation. Move classifications, accuracy scores, evaluation graphs, key moments, and how clearly they are explained.
- Teaching. Explanations in words, coach-style summaries, courses, and video.
- Reference material. Opening databases, master games, endgame tablebases.
Judge a tool on these, not on the engine's name.
The three cost models
Free and open
Lichess is the best-known example: open source, non-profit, no advertising, and funded by donations. Its analysis, studies and opening explorer are available to everyone. Chessblood sits in this group as well, with a different emphasis: the engine runs inside your browser rather than on a server, and the site is built around analysis rather than play.
Freemium platforms
Most large chess platforms offer a free tier with limits and a subscription that removes them. A common pattern is that the free plan allows a restricted number of full game reviews per day, or caps the engine depth, while the paid plan removes the cap and adds lessons and videos. This is a legitimate business model that funds servers and content. The question is simply whether the extras are things you will use.
Desktop GUIs plus a free engine
The traditional route: a desktop program, free or paid, running Stockfish on your own computer. This gives the deepest analysis, because a modern multi-core desktop running the full engine is much faster than any browser build and faster than most shared cloud analysis. Paid desktop products add large databases and annotation tools; free GUIs give you the engine with less polish.
Running Stockfish in the browser
Browser analysis has changed the picture over the last few years. Stockfish compiles to WebAssembly and runs as a worker in the page. The practical consequences:
- Nothing is uploaded. Your game is analyzed on your own CPU. For most people this does not matter; for anyone who cares about privacy, it matters a great deal.
- No queue, no quota. There is no server to pay for per analysis, so there is no reason to limit how many games you review.
- Speed depends on your device. A laptop with several cores does well. A phone is slower and will throttle if the engine runs for long.
This is the model Chessblood uses. The engine is Stockfish 19 with the lite NNUE network, loaded once and cached by your browser. Multi-threading is used where the browser allows it. You can read how the engine evaluates in how Stockfish evaluates positions.
What free analysis cannot do
Being honest about the limits matters more than listing features.
- A browser engine is slower than a desktop one. Depth 18 to 22 per move is realistic for a full game review in a browser; a desktop build will go deeper in the same time. For finding your blunders and mistakes this difference is irrelevant. For deep opening preparation it is not.
- Phones throttle. Long analysis on a mobile device will slow down and drain the battery. A laptop or desktop is the better tool for a full review.
- The engine does not explain. Stockfish tells you what is best, not why. Automated explanations exist, including on this site, but they are pattern-based summaries, not a coach.
- No one is accountable for your improvement. A tool shows you the mistakes. Whether you study them is up to you.
Where paying can be worth it
There are things that genuinely cost money to produce and that free tools do not replicate:
- A human coach. The single most effective investment for most improving players, and nothing on any platform substitutes for it.
- Structured courses and video. Good instructional material takes expert time to make. If you learn well from video, a course can be worth far more than any analysis feature.
- Cloud depth on demand. If you prepare openings seriously and want depth 40 evaluations without owning a fast machine, cloud engine time is a reasonable thing to buy.
- Large curated databases. Millions of annotated master games with search tools are a real product, mostly relevant above club level.
- Supporting a platform you use every day. Paying for something because you want it to exist is a perfectly good reason.
Need by need
Where Chessblood stands
Everything on this site is free, with no premium tier, no advertising and no account. That is a deliberate design decision rather than a promotional phase: because analysis runs in your browser, there is no per-analysis server cost to recover, and the small amount of server work the site does (importing games, storing a report when you choose to share it) is cheap enough to run without charging anyone.
What you get is a full Stockfish game review with move classifications and accuracy, a Stockfish analysis board with multiple lines, import from Chess.com and Lichess, opening guides, puzzles and calculators. What you do not get is coaching, video, or a master database. The free chess analyzer page lists exactly what is included, and the about page explains how the project is run.
A reasonable approach
For most players the sensible order is:
- Use free analysis for every game you play. The engine is the same one you would pay for.
- Spend your money on learning, not on features: a coach if you can afford one, otherwise a good book or course aimed at your level.
- Pay for a platform if you use it daily and want to support it, or if a specific feature such as cloud depth solves a real problem for you.