Byline Pro is a pre-publish quality assurance tool that scans articles for factual accuracy, broken links, and readability issues. Paste your text or fetch by URL, and the pipeline extracts every factual claim, verifies it, validates every link, scores readability, and returns an A-F quality grade in under two minutes.
Founded 2025 | HQ: London | Funding: Bootstrapped | Built by Major Matters
MM Verified
Overview
Byline Pro was built by Major Matters as an internal tool before being released as a standalone product in early 2026. The origin story is simple: after publishing an article with an outdated statistic that a reader caught, the team built an automated checking pipeline to prevent it from happening again.
The product targets newsletter writers, content teams, journalists, bloggers, and students. Anyone who publishes content and wants a systematic check before it goes live. The pipeline runs on Anthropic's Claude API for claim extraction and verification, with concurrent HTTP checks for link validation and Flesch-Kincaid analysis for readability scoring.
Byline Pro currently operates in "Scan" mode (pre-publish QA), with a "Grow" mode (post-publish SEO via Google Analytics and Search Console integration) listed as coming soon. The product is web-based with no installation required.
What We Like
The pipeline is genuinely useful. We ran Byline Pro against 13 articles from major publications including PYMNTS, TechCrunch, Modern Retail, and Payments Dive. It extracted 110 factual claims, identified two genuine inaccuracies (an executive title error and a date mismatch), flagged two broken links, and scored readability across all articles. The errors it found were subtle, exactly the kind that slip past human editors on a third read-through.
Transparent scoring methodology. The composite score weights four factors: fact-check accuracy (50%), link health (25%), readability (15%), and source density (10%). Each factor is broken down in the report, so you know precisely why you received your grade and what to fix. No black box.
Accessible pricing with a genuine free tier. Three free scans per month with the full pipeline, no credit card required. Paid plans start at $12/month for 30 scans. For a solo newsletter writer publishing weekly, the free tier covers most use cases. The pricing is published on the website with no hidden costs.
Speed. A full scan, including claim extraction, verification, link checking, and readability scoring, completes in under two minutes for a typical 800-word article. Fast enough to run as a final step before hitting publish.
What to Watch
Claim verification has knowledge cutoff limitations. Because the fact-checking runs on Claude's language model, very recent claims (published within the last few months) often return as "unverifiable" rather than confirmed or denied. In our testing, 48 percent of extracted claims fell into this category. The tool is strongest on established facts, historical data, and well-documented claims. It is weakest on breaking news.
No CMS integrations yet. Byline Pro works via paste or URL fetch. There is no direct integration with Beehiiv, Substack, WordPress, or Ghost. You cannot trigger a scan from your publishing workflow. This adds a manual step that content teams working at volume may find limiting.
Early-stage product from a small team. Byline Pro is bootstrapped and built by the Major Matters team. There is no dedicated support team, no SLA, and no enterprise tier. The product works well for individual writers and small teams, but organisations requiring compliance guarantees or priority support should set expectations accordingly.
"Grow" mode is not yet available. The SEO performance tracking feature (GA4 and Search Console integration) is listed as "coming soon" on the website. It is not currently functional. Evaluate the product on what it does today, not what it promises.
Pricing and Deployment
Byline Pro offers four tiers: Free (3 scans/month), Writer ($12/month, 30 scans), Pro ($29/month, 100 scans), and Team ($79/month, 500 scans). All tiers include the full analysis pipeline with A-F grading. Deployment is entirely web-based at byline.pro, with no installation, browser extension, or desktop application required. Authentication via email/password or Google OAuth.
Compliance and Security
Byline Pro uses Supabase for authentication and data storage with row-level security. Article text is processed via the Anthropic Claude API for claim extraction and verification. The platform does not store article content after scan completion. No SOC 2 or ISO 27001 certifications are in place. The privacy policy states that submitted content is not used for model training.
Verdict
Byline Pro solves a real problem that most writers deal with manually or not at all: systematic pre-publish fact-checking. The pipeline works, the scoring is transparent, and the price is accessible. For newsletter writers, bloggers, and small content teams who want a quick accuracy check before publishing, it delivers genuine value at the free and Writer tiers.
It is not the right tool for enterprise content operations that need CMS integrations, API access, or compliance certifications. The knowledge cutoff limitation means it works better as a safety net for established facts than as a verification tool for breaking news. As a bootstrapped, early-stage product, expect the feature set to evolve quickly, but evaluate it on what exists today.
Try Byline Pro: byline.pro
How we scored it
| Criterion | Score | Notes |
|---|---|---|
Accuracy & Effectiveness 20% weight | 3.5 | Genuine errors found in real-world testing; knowledge cutoff limits verification of recent claims |
Compliance & Security 15% weight | 2.5 | Supabase RLS, no SOC 2 or ISO certifications; appropriate for content QA, not regulated data |
Documentation 15% weight | 2.5 | FAQ page covers basics; no API docs, no knowledge base, no onboarding guides |
Ease of Setup 10% weight | 4.5 | Web-based, no installation; paste and scan in seconds |
Integration Flexibility 10% weight | 2.0 | No CMS integrations, API, or browser extension; paste or URL only |
Support Quality 10% weight | 2.5 | Email support only; no live chat, no SLA, small team |
Scalability 10% weight | 3.0 | Team tier supports 500 scans/month; no API for programmatic access |
Pricing Transparency 10% weight | 5.0 | All tiers published on website; genuine free tier with no credit card required |
Pros
- The pipeline is genuinely useful
- Transparent scoring methodology
- Accessible pricing with a genuine free tier
- Speed
Cons
- Claim verification has knowledge cutoff limitations
- No CMS integrations yet
- Early-stage product from a small team
- "Grow" mode is not yet available
Editorial disclaimer: Reviews reflect the independent editorial assessment of Major Matters and are not sponsored or endorsed by the companies reviewed. We recommend conducting your own evaluation to determine whether any product is the right fit for your specific requirements.
Charlie Major is a Product Development Manager at Mastercard. The views and opinions expressed in Major Matters are his own and do not represent those of Mastercard.