Fastest deep research APIs in 2026

An answer inside the agent's turn

Many questions an agent asks in the middle of a task have one answer: a name, a date, a number. The SpecStream Search API returns it as answer, with the page that printed it and its read time in seen_at, beside rows with the facts the question asks for. Every reply carries took_ms and price_usd, at $5 per 1,000. Exa's deep-lite is $12 per 1,000 and Parallel's Responses API at low is $10.

curl -s "https://api.specstream.ai/v1/web-search?q=When+did+the+EU+AI+Act+rules+for+general-purpose+AI+models+start+to+apply" \
  -H "Authorization: Bearer $SPECSTREAM_API_KEY" \
  | jq '.data | {answer: .answer.value, page: .answer.page, took_ms, price_usd}'

Measure it yourself in one minute

Every vendor in the table publishes its own times. Time the calls from your own machine instead. The script sends 20 fast searches, each a new question so no answer is reused, and prints the median and the slowest. Then it reads latency_ms for the same calls from your request log. Run the same loop against any other API and compare.

# 20 fast searches, each its own question, timed end to end. Cost: 2 cents.
for i in $(seq 1 20); do
  curl -s -o /dev/null -w '%{time_total}\n' \
    -H "Authorization: Bearer $SPECSTREAM_API_KEY" \
    "https://api.specstream.ai/v1/web-search?speed=fast&q=largest+employer+in+US+county+number+$i"
done | sort -n | awk '{t[NR]=$1} END {print "median", t[int((NR+1)/2)], "s, slowest", t[NR], "s"}'

# The same calls as SpecStream timed them, from your request log
curl -s "https://api.specstream.ai/v1/account/requests?limit=20" \
  -H "Authorization: Bearer $SPECSTREAM_API_KEY" | jq '.. | .latency_ms? // empty'

The fast tier under load

On November 9, 2026 production took 1, 5, 10 and 20 fast searches a second and answered 718 of 720. The median was 0.82 s at 1 search a second and 1.07 s at 20 a second, and the 95th percentile stayed between 1.09 and 1.73 s. A fast call costs $1 per 1,000 for up to 10 results. Add passages=true and the reply carries the text of the top pages closest to the question, chosen by code alone, with pages_wait_ms capping the wait.

Long research comes back as rows, while it runs

A question with hundreds of answers is a list, and a report about it is slow to read and slower to load into a table. Deep Search returns every match on the live web as a structured row, at 5¢, 15¢ or $1 a row, under a maximum you approve first. Your agent reads the rows as they arrive, and the run works until it reaches the count, up to four hours on the largest lists. The searches and pages behind each row are not billed.

Source URL and read time on every value.

Fast and most accurate

The SpecStream Search API scores 97.9 F-score on all 1,000 official SimpleQA Verified questions (978 correct), and 64.0 item F1 and 43.4 row F1 on all 200 official WideSearch tasks. The Extract API reads pages at $0.80 per 1,000 and scores 0.908 F1 on WCXB. Scores and method are on the benchmarks page.

Linkup research

An asynchronous research endpoint that takes 2 to 20 minutes, at a fixed $0.25 to $2.50 a request. The SpecStream Search API returns a sourced answer in a few seconds for $0.005.

Parallel Task API medians

Parallel's own article gives median times from 45 seconds on Lite to 8 minutes on Ultra4x, and 90th percentile times of 1.5 to 11 minutes, at $5 to $1,200 per 1,000 runs. On SpecStream, Deep Search rows can be read while the run goes on.

Gemini Deep Research Max

Google's larger preview agent, estimated at $3.00 to $7.00 a task, with the same 60 minute limit. It does not support structured outputs. SpecStream returns structured rows with the columns you asked for.