EPUB validation is the check that tells you whether an ebook file meets the standard. The tool that does it, EPUBCheck, is used by Amazon, Apple, Kobo and most other stores, and it reports every violation as a coded message: RSC-005 for a schema error, RSC-007 for a missing resource, OPF codes for package problems, NAV and NCX messages for navigation. An EPUB with errors may be rejected outright, may be accepted and display badly or may fail only on one store. Fixing EPUBCheck errors turns a risky file into a reliable one.
Epub Validation Error Fixes · from $189
Epub Validation Error Fixes that makes your EPUB pass EPUBCheck and every store
Epub validation error fixes repairs EPUB validation errors, including EPUBCheck messages, navigation and NCX problems and store rejections, so that the file passes validation and works on every store. A specialist works through your epub validation error fixes job with you, checks each step against the platform's current instructions and confirms the result before you publish, all at a fixed price. Choose a package to see what epub validation error fixes costs for your own book.
View Pricing
Most EPUB validation fix jobs are delivered in about 2 working days.
- EPUBCheck errors repaired
- Nav and NCX fixed
- KDP, Apple and Kobo
Key facts
- $189Starting price for the EPUB validation fix, fixed in advance
- 1 specialistOwns your EPUB validation fix from start to finish
- 2 to 3 daysTypical turnaround for the first review of the EPUB validation fix
Overview
What an EPUB validation fix actually involves
The errors come from a small set of causes. Invalid HTML, such as unclosed tags or attributes that the standard does not allow. References to images, fonts or styles that are missing from the package. A navigation document that is absent or does not match the content. A package file with wrong metadata, a missing identifier or an incorrect modification date. Duplicate IDs. CSS that uses properties unsupported by the standard. Files that are in the package but not listed in the manifest. Most of these are easy to fix once located, and hard to find by hand in a zipped package.
Our service opens the EPUB, runs EPUBCheck and any store-specific checks, interprets every message and repairs each fault in the source files. We fix the HTML, repair the manifest and spine, rebuild the navigation, correct the metadata and tidy the CSS, without changing your text. We then re-run the checks on the repaired file and test it on several apps, including Kindle Previewer, Apple Books and Kobo. You receive a valid EPUB, a short report of every error and its fix and, if you wish, an upload to the store.
We start every EPUBCheck error repair job with an audit. With your EPUB validation fix, we open your file or manuscript, list what is already right, what is wrong and what needs a decision from you, and send that back before any work begins. The audit is why there are no surprises: you know the scope, the price and the schedule, and you know which of markup errors and package errors is likely to need the most care.
The EPUB validation error fix cost is shown in the calculator, and depends on how many errors EPUBCheck reports.
Why it matters
Why an EPUB validation fix matters
EPUBCheck error repair decides whether the work is accepted
A file that does not validate may still open on one device and fail on another, so a pass is the only reliable test. For authors whose EPUB fails EPUBCheck or a retailer's validator, the difference shows in how the finished EPUBCheck error repair work behaves when it is opened, printed or uploaded, not in how it looks on the screen where it was made.
The details carry the quality
Retailers run validators of their own that add rules beyond EPUBCheck. We check each of markup errors, package errors and metadata errors individually, because a fault in one is easy to miss when the rest of the file looks right.
Doing it once, properly, saves time
Fixing errors at the source avoids their reappearance in later edits. Putting markup errors and package errors right once is cheaper than correcting them in every later edition.
EPUB validation error fixes
From red errors to a clean report
EPUBCheck is the standard validator for EPUB files, and a clean report is the starting point for every store. We run your file through the current version, read each message, find the cause in the markup or the package and repair it, then run the validator again until the report is clean.
To fix EPUBCheck errors we deal with the common ones, such as invalid markup, missing resources, wrong media types and duplicate IDs. EPUBCheck RSC errors fix work covers resource and schema messages, and EPUB nav and NCX errors fix work covers the navigation document for EPUB 3 and the NCX file that older readers and some stores still use.
We fix EPUB errors for KDP, for Apple Books and for Kobo, since each store has its own preview and its own extra checks. After the file validates, we test it in Kindle Previewer, Apple Books and Kobo's preview, so that it displays correctly as well as passing the validator.
- EPUBCheck run until the report is clean
- Navigation and NCX repaired
- Previewed in the store tools
Choose the right route
The first decision in an EPUB validation fix
Fix and report
We correct the errors and send the report. It suits files that fail a few checks. We choose this route when the book leans on markup errors, and we show a sample before the whole EPUBCheck error repair job proceeds.
Rebuild and validate
We rebuild the EPUB from clean structure. It suits files with many errors. We choose this route when package errors are central to how the book is used, and we explain the cost and schedule consequences before you commit.
Specification
What we check during your EPUB validation fix
These are the decisions we make on every EPUB validation fix job, and the reason for each one.
What we check
What we do
Why it matters
Errors
Each traced to its cause. We confirm the value with you before building, and record it in the specification for your EPUBCheck error repair job.
Fixed once. Getting this right early avoids rework once the EPUBCheck error repair pages have been proofed.
Markup
Corrected at source. We apply it through a defined style or setting, so it holds across the whole EPUBCheck error repair file.
Does not return. Readers and reviewers notice when it is wrong, even when they cannot say what is wrong in this EPUB validation fix order.
Package
Manifest and metadata corrected. We verify it again in the final proof, because it is easy to disturb during late edits in this EPUB validation fix order.
Consistent file. For your EPUB validation fix, platforms and printers check it automatically, and a failure delays the launch.
Revalidation
Run to a pass. Where your platform sets a different rule, we follow the platform and tell you why with your EPUB validation fix.
Evidence of validity. It also keeps later editions of the EPUBCheck error repair work consistent with the first.
Files
The finished EPUBCheck error repair files, a written report and a short change log, named consistently and delivered with a short specification.
On this EPUB validation fix job, a clear package prevents mix-ups between versions and speeds up any later change. Getting this right early avoids rework once the EPUBCheck error repair pages have been proofed.
Checks
Preflight or validation run on every deliverable, with the report supplied for the EPUB validation fix. We apply it through a defined style or setting, so it holds across the whole EPUBCheck error repair file.
Evidence of a clean pass is what separates a checked file from a hopeful one on this EPUB validation fix project. Readers and reviewers notice when it is wrong, even when they cannot say what is wrong in this EPUB validation fix order.
See what it costs
See the price of your EPUB validation fix in a minute
Pick a package to see what epub validation error fixes costs for your own book, with the delivery estimate and extras shown before you decide.
Build my priceProcess
How an EPUB validation fix job runs
Send
You send the files and tell us what you need from the EPUBCheck error repair job, including where you plan to publish and any deadline. We confirm the scope and the price for the EPUB validation fix. You are never left guessing what comes next, because we confirm each stage of the EPUBCheck error repair job in writing.
Day 1
Audit
We examine the file, list what is correct and what must change, and send a short note with any decisions we need from you for the EPUB validation fix. If something unexpected turns up at this stage, we tell you at once and agree the fix before continuing for the EPUB validation fix.
Days 1 to 2
Plan
We agree the specification, including how we will treat markup errors and package errors, and confirm the schedule. This stage is where most questions arise, so we leave time for them in the schedule on this EPUB validation fix project.
Day 2
Build
With your EPUB validation fix, we carry out the work, applying defined styles and settings, and fixing faults at their source rather than covering them. You are never left guessing what comes next, because we confirm each stage of the EPUBCheck error repair job in writing.
Days 3 to 7
Check
We validate, preview and review the result against the specification, and compare the text with your manuscript in this EPUB validation fix order. If something unexpected turns up at this stage, we tell you at once and agree the fix before continuing for the EPUB validation fix.
Days 8 to 9
Deliver
You receive the files, the specification and the change log, with support if a platform queries the file with your EPUB validation fix. This stage is where most questions arise, so we leave time for them in the schedule on this EPUB validation fix project.
Day 10
Before and after
A publishing job before and after help
The same book, first as an unfinished or failed job and then as a finished one with your EPUB validation fix. For your EPUB validation fix, the manuscript is the same, and only the second is live.
123Before
- 1A validator report in red
- 2A missing navigation document
- 3A file that passes one store only
123After
- 1A clean validator report
- 2A valid nav and NCX
- 3A file that works on every store
- 3problems found in the first review
- 3fixes checked in the final review
- 1named specialist owning every fix
- Fixedprice confirmed in the calculator before you order
A clean report
The validator passes.
A working contents
Navigation works.
Every store
Previews agree.
Pricing calculator
Build your EPUB validation fix price
An EPUB that fails validation can be rejected by Apple Books, Kobo or Amazon, and the errors in EpubCheck are written for programmers. Tell us how many books are affected, which stores they must pass and how the files look now, and the fixed price builds below.
Beyond our online packages? Let us quote it properly.
A catalogue of more than six EPUBs, a fixed-layout or media-overlay EPUB or an EPUB 2 conversion is priced individually so nothing is missed. Send us your files and the validation report, and a specialist replies with a fixed price and delivery date.
The price covers repairing and re-validating the EPUB. New design, cover work, ISBN purchase and printing are not included on this EPUB validation fix project.
Price guide
Epub Validation Error Fixes cost at a glance
The table shows the cost of epub validation error fixes for each package, with the base price, delivery time and the kind of job that fits. The calculator adds extras to your EPUB validation fix for an exact total.
Package
Base price
Standard delivery
Typical book
Review
$189
2-3 working days
Review
Setup
$389
3-5 working days
Setup
Launch
$709
5-8 working days
Launch
A larger or ongoing publishing project
Custom quote
Agreed with your quote
A larger or ongoing publishing project
Comparison
Epub Validation Error Fixes compared with the alternatives
What you compare
A quick EPUBCheck error repair fix
Professional EPUBCheck error repair
Approach
For your EPUB validation fix, a quick fix treats symptoms and leaves the cause in the file. That approach saves effort at the start and tends to cost more in repairs once the EPUBCheck error repair job is live.
A professional EPUBCheck error repair job finds and corrects the cause. We do this as standard on every EPUBCheck error repair job, and the evidence comes with your files.
Consistency
On this EPUB validation fix job, manual changes vary from page to page. It leaves the cause in place, so the same fault tends to return when the text changes with your EPUB validation fix.
Defined styles apply identically everywhere. It is built to be repeated, so later editions cost less and match the first on this EPUB validation fix project.
Validation
On this EPUB validation fix job, success is judged by eye on one screen. It is hard to check, so faults are usually found by readers instead of by the author in this EPUB validation fix order.
Success is judged by the platform's own checks and real devices with your EPUB validation fix. For a EPUB validation fix, it is checked by a person and by software before it reaches you, so problems are found early.
Documentation
Nothing is recorded, so the next edition starts again for the EPUB validation fix. That approach saves effort at the start and tends to cost more in repairs once the EPUBCheck error repair job is live.
A specification and change log are supplied in this EPUB validation fix order. We do this as standard on every EPUBCheck error repair job, and the evidence comes with your files.
Risk
A rejected upload costs days and may delay a launch for the EPUB validation fix. It leaves the cause in place, so the same fault tends to return when the text changes with your EPUB validation fix.
Files are tested before they reach you, and fixes are covered by the guarantee on this EPUB validation fix project.
Cost
Cheap at first, then repeated whenever something changes with your EPUB validation fix. It is hard to check, so faults are usually found by readers instead of by the author in this EPUB validation fix order.
With your EPUB validation fix, a fixed price and a reusable result. For a EPUB validation fix, it is checked by a person and by software before it reaches you, so problems are found early.
Our standard
The standard we hold every EPUB validation fix to
Fix causes, not symptoms
Our EPUBCheck error repair work corrects the underlying structure, so the same problem does not return when the text changes. It is a standard we hold on every EPUBCheck error repair job, whatever the price of the package or the length of the book.
Evidence over assurance
For a EPUB validation fix, we supply the validation or preflight report with your files, so a clean result is something you can see. You can check it for yourself, because the evidence comes with your files in this EPUB validation fix order. Holding to it costs us time, and it saves you the cost of repairs later with your EPUB validation fix.
Plain communication
We explain what we found and what we did in plain language, and we tell you honestly when something is outside what the file can support in this EPUB validation fix order. Holding to it costs us time, and it saves you the cost of repairs later with your EPUB validation fix.
Checklist
The pre-delivery checklist for an EPUB validation fix
Every item below is verified on your EPUB validation fix before it leaves our desk.
- Audit completed and agreed with you
- Markup errors checked and corrected
- Package errors checked and corrected
- Metadata errors checked and corrected
- Warnings checked and corrected
- Validation or preflight run with the report supplied
- Previewer and device checks completed
- Text compared with the approved manuscript
- Specification and change log delivered
How we work
How we approach an EPUB validation fix
Structure first
In EPUBCheck error repair, markup errors and package errors are built into the file, not painted on top. We treat structure as the foundation and appearance as the finish, because structure is what survives edits and platform changes for the EPUB validation fix.
Checked, not hoped
A file is not finished because it looks right on our screen for the EPUB validation fix. It is finished when the validator, the preflight and real devices agree, and when we can show you the evidence on this EPUB validation fix project. It is the principle behind most of what we do on EPUBCheck error repair, and the reason we prefer to explain our choices rather than hide them.
Your files stay yours
We deliver source files and a specification, and we never lock your EPUBCheck error repair work inside a proprietary format. For a EPUB validation fix, if you hire someone else later, they can pick up where we stopped. It is the principle behind most of what we do on EPUBCheck error repair, and the reason we prefer to explain our choices rather than hide them.
Client reviews
What authors say about our epub validation error fixes
Verified reviews from authors who used our epub validation error fixes service.
Good publishing support overall. The KDP metadata setup was thorough. One category selection needed updating after initial launch but it was corrected promptly. The book is performing well in its target categories.
Navigating IngramSpark's requirements for the first time felt overwhelming. The upload assistance handled everything — metadata, pricing setup, distribution channels. My children's book reached bookstores within two weeks.
My KDP file was rejected with a technical error message I could not understand. Book Formatting Experts diagnosed the problem immediately — a bleed issue on three pages — and corrected it the same day. Approved first time.
My YA novel needed to reach both English-language and Japanese readers. The multi-region distribution setup was handled correctly across all required platforms. International sales have exceeded my expectations.
My cookbook needed to be set up across multiple platforms simultaneously. The publishing support team handled every submission — KDP, IngramSpark, and Apple Books — with different requirements for each. Flawlessly executed.
Good support throughout the KDP upload process. The metadata setup and category selection were explained clearly. One pricing setting needed adjustment after initial setup but it was corrected quickly.
As a first-time author, the technical side of self-publishing was genuinely daunting. The consultation covered every decision — platform choice, pricing strategy, metadata, and distribution. I launched with genuine confidence.
Getting historical fiction placed in the right categories on Amazon and IngramSpark required strategic metadata. The team understood the genre classification and the book reached the right readers from the first week.
The formatting error fix service saved my launch. My original formatter had made margin errors causing repeated rejection. Book Formatting Experts identified and fixed every issue within 48 hours. My launch was back on schedule.
The publishing readiness review identified four issues in my manuscript that would have caused rejection. Each was clearly explained and quickly resolved. My book launched without any technical complications.
The website reflects the quality of my coaching work and the seriousness of my brand. The blog setup is easy to manage and the book landing page converts well. I am proud to share it with everyone I meet.
The website positions me as an authority in my field without feeling stiff or corporate. The testimonials section, media page, and book overview all build credibility effectively. Exactly what a nonfiction author needs.
The dark, atmospheric design matches the tone of my crime novels without feeling clichéd. New readers understand the genre and mood of my work immediately from the homepage. My ebook sales from website referrals increased by 60%.
Good website design overall. The mobile experience is excellent. I requested a few content changes after delivery which were handled efficiently. My reader newsletter opt-ins have increased noticeably since launch.
The cover honours the cultural themes of my book while appealing to an international readership. The imagery, colour palette, and typography choices were all discussed through a genuinely collaborative process.
Literary fiction covers require a completely different approach from genre fiction. The design is elegant, restrained, and communicates the literary quality of the book. I am genuinely proud to show it to readers.
My thriller needed a cover that was unsettling without being gratuitous. The designer found exactly the right tone. The typography treatment adds to the unease in a subtle, effective way.
Really good cover design. The atmospheric quality matched my book's tone well. I requested one colour adjustment in revisions which was done quickly. The final cover looks exactly like a major publisher's release.
FAQ
Epub Validation Error Fixes: questions answered
These are the questions authors ask most about epub validation error fixes, including steps, errors and cost. If your question about the EPUB validation fix is missing, request a quote and a specialist will reply.
How do I fix EPUBCheck errors?
Read each message, locate the fault in the file and correct it, then run EPUBCheck again. For EPUBCheck error repair, we check the result against the platform's own rules before you see it.
What is EPUB validation error repair?
It is the correction of the faults that EPUBCheck reports. We keep a record of what we changed so that you can review the work with your EPUB validation fix.
Can you fix EPUB errors for KDP?
Yes. We validate and test with Kindle Previewer. The calculator on this page shows the fixed price for each package before you commit on this EPUB validation fix project.
Can you fix EPUB errors for Apple Books?
Yes. For your EPUB validation fix, if you are unsure, send the file and we will tell you what the job involves.
Can you fix EPUB errors for Kobo?
Yes. Revision rounds are included, so the first delivery does not have to be perfect on this EPUB validation fix project.
What are EPUBCheck RSC errors?
They are resource and schema errors, such as RSC-005 and RSC-007. For EPUBCheck error repair, we check the result against the platform's own rules before you see it.
What are EPUB nav and NCX errors?
They are faults in the navigation files that list the contents. We keep a record of what we changed so that you can review the work with your EPUB validation fix.
How much does EPUB error repair cost?
The calculator on this page shows a fixed price for each package on this EPUB validation fix project. The calculator on this page shows the fixed price for each package before you commit on this EPUB validation fix project.
Will you change my text?
No. We change structure only. For your EPUB validation fix, if you are unsure, send the file and we will tell you what the job involves.
Can you upload the repaired file?
Yes, on request. Revision rounds are included, so the first delivery does not have to be perfect on this EPUB validation fix project.
What if the file passes EPUBCheck and still fails?
We investigate the store's message. For EPUBCheck error repair, we check the result against the platform's own rules before you see it.
How long does it take?
Most repairs take about four days. We keep a record of what we changed so that you can review the work with your EPUB validation fix.
How do I fix EPUBCheck errors?
Trace each error to its cause in the source, correct it and revalidate. We do this. The calculator on this page shows the fixed price for each package before you commit on this EPUB validation fix project.
What is EPUB validation error repair?
Fixing the faults a validator reports so that the file passes. For your EPUB validation fix, if you are unsure, send the file and we will tell you what the job involves.
Do you offer an EPUB validation error fix service?
Yes. Revision rounds are included, so the first delivery does not have to be perfect on this EPUB validation fix project.
How much does epub validation error fixes cost?
The epub validation error fixes cost starts at $189 for a review and rises to $709 for a complete launch package. Epub validation error fixes services and epub validation error fixes cost depend on the platform and the amount of work, and the calculator shows the total.
How long does epub validation error fixes take to finish?
Most EPUB validation fix jobs are delivered in about 2 working days. For a EPUB validation fix, priority options shorten the schedule, and the calculator shows an estimate.
Ready when you are
Ready to start your EPUB validation fix?
An EPUB that validates and previews cleanly goes through every store the first time. See your price in a minute, or send the file and we will confirm what to fix.
- Fixed price shown before you pay
- Revision rounds included
- One named specialist, brief to upload