Software Alternatives & Startups

ALTCHA VS Stract API

Compare ALTCHA VS Stract API and see what are their differences

ALTCHA

ALTCHA is a free CAPTCHA alternative that uses a proof-of-work mechanism to protect your website, and online services from spam.

Rating
0 reviews
Pricing
Open source Free
Stract API

Upload PDFs, office docs, or scans, describe the data you need in plain language, and get a spreadsheet, CSV, or JSON back. No manual entry, no brittle templates.

Rating
0 reviews
Pricing
Paid Free trial
Note: These products don't have any matching categories. If you think this is a mistake, please edit the details of one of the products and suggest appropriate categories.

Which is more popular?

Based on our record, ALTCHA seems to be more popular. It has been mentioned 4 times since March 2021.

social mentions
4 vs 0
SPAM Protection popularity
100% vs 0%
alternatives listed
49 vs 1

Base details

Website, pricing, platforms and company facts side by side.

ALTCHA
Stract API
Website altcha.org stract-api.com
Pricing
Open source Free
Paid Free trial Official pricing
Platforms
Web REST API
Browser REST API
Company — Startup from the United States · 1 - 9 employees · 2026
Listed in

About ALTCHA and Stract API

In their own words, as submitted to SaaSHub.

ALTCHA
Stract API

ALTCHA uses a proof-of-work mechanism to protect your website, APIs, and online services from spam and unwanted content. Unlike other solutions, ALTCHA is free, open-source and self-hosted, without external services, does not use cookies nor fingerprinting, does not track users, and is fully...

Read more about ALTCHA

No description of Stract API yet.

Features and specs

What each product offers, as listed by its team.

ALTCHA 9 features
Stract API 0 features
  • Privacy-friendly, GDPR compliant
    No cookies, no tracking, no external servers.
  • Frustration-free
    No visual puzzles. PoW Captcha is better for people.
  • Spam Filtering
    Employs machine learning to categorize submitted data and identify unwanted messages.
  • Open-source
    Free to use, free to modify. MIT licensed.
  • End-to-End Encryption
    The Encryption Shield mitigates data breaches by encrypting data with asymmetric end-to-end encryption.
  • Digital e-Signatures
    e-Signatures made easy with eIDAS-compliant simple and advanced signatures - qualified digital certificates and DigiDoc.
  • Visual Form Builder
    Create custom forms effortlessly with the visual form builder, empowering users to design tailored solutions without any coding expertise.
  • File Attachments
    Safely request and securely store file attachments with end-to-end encryption, ensuring the utmost protection for your data.
  • Send to Email or Webhook
    Configure forms to seamlessly send data to email, APIs, or webhooks using processors, facilitating efficient data handling and integration with your workflows.

No features have been listed yet.

Category popularity

How often each product is chosen within a category, 0–100% relative to the other.

Score bands 0–20 21–40 41–50 51–60 61–100
ALTCHA
Stract API
100% 100%
0% 0%
0% 0%
100% 100%
100% 100%
0% 0%
0% 0%
100% 100%

Questions & Answers

As answered by people managing ALTCHA and Stract API.

What makes your product unique?

ALTCHA's answer

What makes ALTCHA unique is that it is free, open-source and self-hosted, without external services, does not use cookies nor fingerprinting, does not track users, and is fully compliant with GDPR. Unlike other captcha solutions, ALTCHA does not require users to solve puzzles or captchas and uses a proof-of-work mechanism instead.

Stract API's answer:

Stract API is different because it lets the people closest to the questions get answers straight from their documents, with no templates, no custom tooling and no manual data entry. You upload your files, describe the data you need in plain language, and Stract API runs every document in the batch from start to finish. It returns clean, structured results you can put to work right away. You choose the model that fits the job, from fast, economical options for high-volume work to the newest, most capable LLMs for your highest-stakes analysis. Under the hood, it draws on techniques from the latest AI research to improve the quality of what gets extracted. The same analysis costs less than 10% of the equivalent staff time, so your team can skip the grind and go straight to analysis. And because sensitive work is the norm for many of your users, Stract API is fully SOC2 compliant, so your documents stay yours.

Why should a person choose your product over its competitors?

ALTCHA's answer

Here are some key reasons why a person should choose ALTCHA over its competitors:

  • Privacy compliance - ALTCHA is fully compliant with privacy regulations like GDPR since it does not use cookies, fingerprinting or track users. This is a major advantage over other captcha solutions.
  • Open source and self-hosted - ALTCHA is free, open source software that can be self-hosted without relying on external services. This gives more control and independence to the user.
  • Accessible design - ALTCHA uses a proof-of-work mechanism instead of puzzles or captchas, making it more friendly and accessible for humans. Captchas can be difficult for some users.
  • Machine compatibility - ALTCHA is designed to also work for machines and APIs, making services accessible for bots and automated systems. Other solutions may not be as compatible.
  • Modern approach - ALTCHA represents a privacy-first, inclusive approach to spam protection as opposed to traditional captcha methods. This future-proofs the solution.
  • Effective spam filtering - In addition to proof-of-work, ALTCHA also offers an effective spam filter module to block sophisticated spam attacks. This provides comprehensive protection.

So in summary, ALTCHA's privacy compliance, open design, accessibility, machine compatibility and modern approach give it clear advantages over competing captcha solutions.

Stract API's answer:

A person should choose Stract API over its competitors because it gets them from a pile of documents to usable data with the least effort and risk. They describe what they need in plain language, so they don't build templates or learn a tool's vocabulary. They can use the point-and-click UI or the API for automated workflows, so the same product works for a one-off project and for a recurring pipeline. They also keep control over the tradeoff that matters most to them. They pick the model for each job, from fast, economical options for high-volume work to the newest, most capable LLMs for high-stakes analysis, instead of paying top-tier prices for everything. The extraction itself uses techniques from the latest AI research to improve quality. The cost is under 10% of the equivalent staff time, and results come back fast even on huge batches. Finally, Stract API is fully SOC2 compliant, which matters to teams handling case files, sources and survey data. Together, that means a team clears its "Needs Attention" pile and gets to analysis faster, without trading security or depth for speed.

Which are the primary technologies used for building your product?

ALTCHA's answer

JavaScript and Svelte.

Stract API's answer:

The primary technologies used in build Stract API are LLMs, Typescript, React, and Java.

How would you describe the primary audience of your product?

ALTCHA's answer

Our primary audience for ALTCHA Forms includes enterprises, medium and small businesses, non-profits, and individuals who need a reliable, secure, and compliant solution for data collection and management. Whether you're a large corporation dealing with extensive regulatory requirements, a small business looking to protect customer and employee data, a non-profit organization managing sensitive information, or an individual seeking robust data security, ALTCHA Forms provides the tools and features necessary to meet your needs. With a focus on compliance, user-friendly design, and advanced security measures, our platform is tailored to support diverse users in navigating complex regulatory landscapes and ensuring data protection.

Stract API's answer:

The primary audience for Stract API is small-to-mid-sized teams, along with enterprises, that run recurring, document-heavy workflows and need to pull consistent information out of growing batches of files faster than manual review allows. These teams are typically staff-constrained, facing rising intake volumes of contracts, case files, forms or survey responses, and working from question lists that keep changing over time. Buyers tend to be operations leaders, legal and contract review leads, insurance claims intake leads, research leads, marketing and CRM operations managers, and engineering teams responsible for pipeline automation. Day-to-day users include the document reviewers who need the extracted information and the developers and analysts who feed that structured output into downstream systems. The audience spans insurance and claims, legal (contracts, discovery and case files), journalism (FOIA releases, court records and meeting minutes), marketing (reviews, support tickets and call transcripts), social science (surveys, interviews and field notes) and academic research. Stract API is a weaker fit for organizations that only need occasional one-off extraction from a handful of documents, or teams committed to strictly template- or regex-driven extraction rather than plain-language field specifications.

Who are some of the biggest customers of your product?

Stract API's answer:

Legal services and title companies are growing segments for Stract API

What's the story behind your product?

Stract API's answer:

Stract API grew out of founder Matt Moreno's repeated frustration with the same problem. At a construction tech startup in Google's accelerator, his team built an LLM feature that matched a crew's plain-language daily report to labor and material options. It worked, but it was fragile. Parsing the output was hard, bad output was constant, and any change to the structure broke it. When he asked a Google director whether a product existed to extract arbitrary structured data from unstructured text, the director said no, but that Google probably should build one. Later, on a venture to automate land title research, he again spent tens of hours building flexible document extraction. That work pulled him away from the core mission, and he wished a third-party service would handle it. When he had time this summer (2026), he found few existing solutions. Remembering the director's words, he built Stract API, which took five months to reach MVP. It lets users describe the information they want, from simple facts to judgment-heavy analysis, and returns a spreadsheet, CSV or JSON from their documents.

User comments

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Social recommendations and mentions

Recommendations tracked on public social media and blogs since March 2021.

ALTCHA 4 mentions
Stract API 0 mentions
  • Self-Hosted Proof of Work with ALTCHA: A Turnstile Alternative for Magento
    ALTCHA won on the boring things. It is open source, self-hosted and collects nothing, and it ships official libraries in both Go and PHP, the two languages our two layers already speak. So the same protocol runs twice on every store, by... - Source: dev.to / about 1 month ago
  • A self-hosted Google reCAPTCHA alternative (we ship it)
    The captcha on orkestr is Altcha. Self-hosted, no third-party JS, no Google, no behavioral tracking. Users don't see a puzzle. There's a single checkbox and a quiet "verifying..." while the browser does some math. About a second, total. - Source: dev.to / 6 months ago
  • Why Proof-of-Work Beats CAPTCHA for Form Protection
    Here's how PoW works for form protection (using the ALTCHA wire format):. - Source: dev.to / 8 months ago

View more

Tracking Stract API since Nov 2026.

Alternatives to ALTCHA and Stract API

When comparing ALTCHA and Stract API, you can also consider the following products.