Free API 510 PDF for the 2026 to 2027 exam windows

Download the free 2026 to 2027 quick reference

No email, no sign-up, no landing page in between. Eight pages written for the September 2026 to May 2027 exam windows: the format, where the marks actually sit, every formula the paper leans on, the interval rules, and ten questions with the full reasoning.

It is designed to be printed and kept, or read on a phone on the way in.

What you probably came here for

Most people searching for an API 510 PDF want one of two things: a free copy of the code itself, or something useful they can download today.

The second one is above. The first one is worth being straight about, because the honest answer changes what you should do next.

What you actually need, and in which edition

The exam is written against a published list of documents, each pinned to a specific edition. Studying the right document in the wrong edition is the single most expensive mistake in this whole process, because everything reads correctly and some of your answers are quietly out of date.

For the exam windows running from September 2026 to May 2027, the basis is the inspection code in its 11th edition from October 2022, carrying both of its correction notices, the second of which arrived in 2025.

Around it sit a set of recommended practices and three sections of the boiler and pressure vessel code, and those construction and examination volumes rolled forward to their 2025 editions for this cycle.

• The inspection code itself, 11th edition, with both errata
• Damage mechanisms, though only fifteen named ones are examinable
• Inspection practices for pressure vessels
• Inspection of pressure-relieving devices
• Welding processes, inspection and metallurgy, with its own correction notice
• Material verification programmes
• Three sections of the boiler and pressure vessel code, 2025 editions
• The repair practices document, in its 2022 edition

About the free PDFs

There is a large supply of these documents floating around as free downloads. They are not hard to find and this page is not going to pretend otherwise.

What is worth knowing is why they are usually a bad deal even setting the legality aside. Copies that circulate freely are old, because a document has to have been out for years before it leaks widely. Old is precisely the problem here: the numbers, tables and acceptance criteria you are being tested on are the ones in the current edition, and a superseded copy will teach you the previous answer with total confidence.

The second problem is that they are rarely complete. Scanned copies drop annexes, and the annexes are where several examinable rules live.

What is genuinely free and worth having

A surprising amount of the surrounding material is free and legitimate, and most candidates never look for it.

The publications effectivity sheet and the Body of Knowledge are both free. Between them they tell you exactly which editions apply and exactly what is examinable, which is more decision-useful than the documents themselves when you are planning study.

Committee change summaries and errata notices are also generally free, and an errata notice is often a single page that tells you precisely what moved.

• The publications effectivity sheet for your exam window
• The Body of Knowledge, which is the list of what can be asked
• Errata notices, which are short and tell you what changed
• Candidate handbooks and application guidance

You do not carry any of it into the exam

This catches people out. The open book half of the paper supplies its references as PDFs on the exam computer. You cannot bring your own printed copies, your own tabs, or your own notes.

That changes what owning the documents is for. You are not building a reference set to carry in on the day. You are building familiarity, so that when a question lands you already know roughly where the answer lives and can find it on an unfamiliar screen under time pressure.

It also means the tab-and-highlighter ritual, which is genuinely useful for some exams, buys you much less here than people expect.

How to get them without paying twice

Ask your employer first. Refineries, inspection contractors and engineering firms very often hold current subscriptions or a library copy, and the person who administers it is used to being asked.

If you are buying, buy against the effectivity sheet rather than against whatever the store is promoting, and buy the individual documents you need rather than a bundle that includes several you are not tested on.

The construction and examination volumes are the expensive part by a wide margin, so if there is one thing to chase down internally rather than buy, it is those.

• Ask about an existing subscription before you buy anything
• Buy to the effectivity sheet, not to the newest edition on sale
• Buy documents individually rather than as a package
• Check whether a training provider includes access in the course fee

Do you actually need all of them?

You are tested on all of them, so you need access to all of them at some point. Whether you need to own all of them is a different question, and for most candidates the answer is no.

A realistic pattern is to own or borrow the inspection code, because you will live in it, and to get access to the rest for long enough to work through the parts the Body of Knowledge actually names. Several of the recommended practices contribute only a handful of questions each.

That is also the argument for practising against a large question bank rather than reading cover to cover. Questions tell you where your gaps are. A document does not.

If you would rather work from paper

Some people revise better from a book than a screen, and a question bank on paper is easier to annotate.

API 510 Study Companion covers the same ground as the app in print: the Body of Knowledge explained in plain terms, 613 practice questions and a full mock exam. It is a study aid rather than a substitute for the referenced documents, same as everything else on this page.