Sigma AI reviews · researched 5 Nov 2026
Is Sigma AI legit?
Mostly. Sigma AI is a real Madrid data company, founded in 2008 with offices in London and Miami, but it publishes no freelance rates or payment terms, and its few public worker reviews are mostly negative. Its job posts state no pay, applicants report unpaid tests that go unanswered, and workers describe per-minute transcription pay and one-sided contract terms, so ask for the rate and read the contract before you invest time.
- Trustpilot2.6/57 reviews
- Trustpilot (sigma-ai.com)2.2/58 reviews
- Read 5 Nov 2026
The Sigma AI review
Researched Nov 2026 · 14 sourcesIt pays Not stated; Madrid transcribers report ~€7–€9/hr (Glassdoor) (third-party reports).
Listed in our live directory
Daniel Tapias (CEO) and Nuria Gómez Bermejo (CFO) founded Sigma in Madrid in 2008; it also has offices in London and Miami. It collects and annotates speech, text, image and video data for AI, now also sells AI evaluation, and shows Google, Microsoft, AWS and Samsung among its clients. Read on 5 November 2026, its own pages differ on size (2,500+ to 70,000+ people, 200+ to 700+ languages), and 86 of its 88 job posts claim over 30 years of experience.
Remote linguists work as freelancers under a commercial contract. None of the 88 posts on its careers feed on 5 November 2026 states a rate, and Sigma publishes no payment schedule or method. Reviewers describe low pay per minute of transcribed audio; one says payments are regular, while others report unpaid work.
Trustpilot 2.6/5 (7 reviews) · Trustpilot (sigma-ai.com) 2.2/5 (8 reviews). Read November 2026.
Language-driven: each posting asks for fluent or native speakers of a named language, a few for a pair or trio (Czech and English, Korean and Japanese; German, Russian and English). Of its 88 postings on 5 Nov 2026, 72 are tagged Fully Remote, 15 are on-site in London and 1 in Madrid (careers.sigma.ai/jobs.json). Its postings describe offices in Spain, the US and the UK.
No Sigma-specific impersonation cases turned up in a web search on 5 November 2026. Real openings are listed at careers.sigma.ai, and Sigma's job posts say it never hires through agents or other third parties. Other companies share the Sigma name, so check the domain is sigma.ai. Never pay to get work; fake recruiters often start on text, WhatsApp or Telegram.
What people praise
- One reviewer, posting in September 2025 and again in January 2026, praises supportive managers and regular payments.
- Work is remote on a platform open around the clock, and many projects ask only for fluency in the languages and basic computer skills.
What people complain about
- Applicants say they transcribed test audio (one says five files) and then heard nothing back, or got no answer to questions about a confusing test.
- A June 2026 reviewer says his wife, paid per minute of transcribed audio, sat unpaid meetings, lost work to crashes and had not been paid for about 80 hours over two weeks.
- A second Trustpilot profile, for sigma-ai.com (which redirects to sigma.ai), has 8 reviews, all 1-star, reporting pay of $2 to $3 an hour, a recording project cut short after 75 files and work never paid.
- A December 2025 reviewer says the contract came through Sigma's US office with one-sided clauses, and urges legal advice before signing. Sigma has not replied to any review.
Best for: Native or fluent speakers of the languages Sigma recruits for (many Indian, Asian and European languages) who want occasional remote transcription, annotation or recording work. Not for: Anyone who wants to know the rate before spending hours on tests, needs predictable income, or is not ready to read a freelance contract closely.
Honest catches
- Pay here is third-party reports, not measured live from a job feed, so treat it as a benchmark rather than a guaranteed rate.
Sources for this review
- Sigma AI: About (founders, headquarters, 25K+ annotators, 500+ languages; read November 5, 2026)
- Sigma AI: FAQs (founded 2008 in Madrid, offices, 500+ languages; read November 5, 2026)
- Sigma AI: homepage (18+ years, 70K+ experts, 700+ languages, clients, AI data and evaluation; read November 5, 2026)
- Sigma AI Careers (Madrid, London and Miami, more than 2,500 people; read November 5, 2026)
- Sigma AI Careers: job feed (88 posts, read November 5, 2026)
- Sigma AI Careers: Cantonese Chinese (Traditional script) Linguistic Projects (Remote), posted October 19, 2026
- Sigma AI Careers: Swedish Linguistic Projects (On-site London), posted October 27, 2026 (200+ languages)
- Trustpilot: sigma.ai reviews
- Trustpilot: sigma.ai reviews, all languages
- Trustpilot: sigma.ai 5-star reviews, all languages
- Trustpilot: sigma-ai.com reviews (profile named Sigma Technologies)
- Trustpilot: sigma-ai.com reviews, all languages
- sigma-ai.com (redirects to sigma.ai, checked November 5, 2026)
- FTC Consumer Alert: That job offer text is probably a scam (April 30, 2026)
Got a message from Sigma AI?
Its real sites: sigma.ai. Paste the message to check the links, the sender and the pay.
What Sigma AI's job board shows
Read from its public job board every hour: how much it lists, how often it states pay, who may apply and how fast roles come down, against every other platform this site reads.
No listings by Sigma AI were read from 14 Oct 2026 to 10 Nov 2026; the other platforms had 0 open roles on 10 Nov 2026.
Sigma AI against the other platforms
How does Sigma AI compare with the rest of the market on size, pay, reach and turnover?
| Measure | Sigma AI | Other platforms | Its rank (1 = highest) |
|---|---|---|---|
| Open roles on 10 Nov 2026 | 0 | 0 | n/a |
| Share of all open roles | n/a | n/a | n/a |
| New listings in the window | 0 | 0 | n/a |
| Kinds of work listed | 0 | 0 | n/a |
| Open roles stating an hourly rateSmall sample | n/a | n/a | n/a |
| Median advertised paySmall sample | n/a | n/a | n/a |
| Open roles accepting any countrySmall sample | n/a | n/a | n/a |
| Median days listed, removed rolesSmall sample | n/a | n/a | n/a |
Sigma AI reviews: questions
Is Sigma AI legit?
Mostly. Sigma AI is a real Madrid data company, founded in 2008 with offices in London and Miami, but it publishes no freelance rates or payment terms, and its few public worker reviews are mostly negative. Its job posts state no pay, applicants report unpaid tests that go unanswered, and workers describe per-minute transcription pay and one-sided contract terms, so ask for the rate and read the contract before you invest time.
Is Sigma AI a scam?
No. Sigma AI is a real company. No Sigma-specific impersonation cases turned up in a web search on 5 November 2026. Real openings are listed at careers.sigma.ai, and Sigma's job posts say it never hires through agents or other third parties. Other companies share the Sigma name, so check the domain is sigma.ai. Never pay to get work; fake recruiters often start on text, WhatsApp or Telegram.
Does Sigma AI pay?
Yes. Genuine flexibility, but worker sentiment on pay is mixed-to-negative. Payouts: Freelance commercial contract; its postings and careers site publish no payment method or schedule (read 5 Nov 2026). Remote linguists work as freelancers under a commercial contract. None of the 88 posts on its careers feed on 5 November 2026 states a rate, and Sigma publishes no payment schedule or method. Reviewers describe low pay per minute of transcribed audio; one says payments are regular, while others report unpaid work.
What do workers say about Sigma AI?
Trustpilot 2.6/5 (7 reviews) · Trustpilot (sigma-ai.com) 2.2/5 (8 reviews), read November 2026. Praise: One reviewer, posting in September 2025 and again in January 2026, praises supportive managers and regular payments. Complaints: Applicants say they transcribed test audio (one says five files) and then heard nothing back, or got no answer to questions about a confusing test.
How do I spot a fake Sigma AI recruiter?
No Sigma-specific impersonation cases turned up in a web search on 5 November 2026. Real openings are listed at careers.sigma.ai, and Sigma's job posts say it never hires through agents or other third parties. Other companies share the Sigma name, so check the domain is sigma.ai. Never pay to get work; fake recruiters often start on text, WhatsApp or Telegram.
Who is Sigma AI for?
Best for: Native or fluent speakers of the languages Sigma recruits for (many Indian, Asian and European languages) who want occasional remote transcription, annotation or recording work. Not for: Anyone who wants to know the rate before spending hours on tests, needs predictable income, or is not ready to read a freelance contract closely.
More on Sigma AI
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- Sigma AI: overview and live roles
- Sigma AI Hiring Data (research report)
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