AI memory comparison
Tephra vs Mem0
Mem0 is memory infrastructure for developers, with an open-source version and a free plan. Tephra is a hosted memory that your connected AI apps share. If you are building an app that needs memory, Mem0 is the closer match. If you want your own AI tools to share one memory without writing code, Tephra is.
Sources read and prices checked 2026-10-10.
Obsidian Metrics makes Tephra and Tracker, the two products this page compares against others. This page is written by the maker of one of the products compared, so read the competitor columns against their own pages, linked below each table. Competitor facts come only from the vendor pages listed under Sources, read on the date shown above; vendors change plans and prices without notice. We are not affiliated with any company named here, and all product names belong to their owners.
Tephra and Mem0 side by side
| Feature | Tephra | Mem0 |
|---|---|---|
| What it is | A hosted memory your connected AI apps share: they recall from it and write to it over MCP or REST. | Persistent memory for AI applications, sold as a managed platform and as an open-source library or Docker stack. Aimed at developers building AI apps. [1] |
| Entry price | Tephra needs a paid plan: Premium at $19 a month in the Obsidian Metrics Skool community or $29 a month direct, or a $399 one-time seat. No free tier. | Hobby is free (10K add requests and 1K retrieval requests a month). Starter is $19 a month, Pro is $249 a month, Enterprise is custom. [2] |
| How usage is limited | No usage metering. There are only abuse limits: 60 requests a minute per key and 120 a minute per member. | Metered by add and retrieval requests per month on each plan; usage-based pricing is also offered. [2] |
| Reach across AI apps | One memory for every AI you connect, led by OAuth sign-in: the Connect page has steps for Claude (web, Desktop, mobile), ChatGPT, VS Code Copilot, Cursor, Claude Code, Gemini CLI, Windsurf, Zed, Mistral Le Chat and Perplexity, plus generic steps for any other MCP app, and a personal key as a fallback, plus REST. AI tools that support neither MCP nor REST calls cannot connect. Tephra's OAuth discovery endpoints were verified live on 2026-10-10. | Documentation lists setup guides for 22 tools, including LangChain, CrewAI, LlamaIndex and the Vercel AI SDK, and coding-agent guides starting with Claude Code, then Cursor, Codex and others. [1] |
| Seeing and correcting what is stored | A member can view memories, edit or delete them, read edit history, contest a memory, export their own data (app session), and revoke any AI key with an activity log. | The docs navigation links to a developer dashboard; the landing page we read carries little else. Controls for end users are not described on the pages we read. [1] |
| Hosting and self-hosting | Hosted service run by Obsidian Metrics. Self-hosting is not part of the product. We make no encryption-at-rest or compliance-certification claim. | Open-source version runs as a library or Docker stack on your infrastructure, or use the managed platform. Enterprise lists on-prem deployment, audit logs and SSO; the site shows SOC 2 Type I and HIPAA Ready badges. [1] [2] |
| How memories get in | The connected AI writes them by calling a remember tool. Tephra does not capture chats automatically and has no Gmail, Slack or Drive connectors. You can upload text, markdown, JSON, XML and text-layer PDF files. | Developers save and search memories through the API or library. [1] |
Where Mem0 is better
- Mem0. You can run the open-source version on your own infrastructure, and there is a real free plan for prototyping. Tephra has neither. [1] [2]
Choose Mem0 if: You are a developer adding memory to your own application, you want to self-host, or you want a free plan to prototype.
Where Tephra is better
- Connected AI apps read and write the same memory directly, rather than moving it between apps by pasting text. Claude's import and export, for example, works by pasted text, and its import path is marked experimental.
- A flat price with no usage metering, instead of credits or request quotas.
- A shared library that Tephra grows every hour from public research and regulatory sources, included with the product. We did not find a competitor that bundles one; that is a qualitative check, not an exhaustive market survey.
- Recall in the app tells you which related memories it did not load and how complete the answer looks.
Choose Tephra if: You use several AI apps or accounts and want them to share one hosted memory without building anything, and a flat price matters more than a free tier.
Where Tephra falls short
- Tephra has no free tier and no self-hosted option.
- The MCP tools return ranked records only. The completeness alert is shown in the app, not through MCP.
- No automatic chat capture, and no connectors to Gmail, Slack or Drive.
- No image or audio ingest, and no OCR for scanned PDFs.
- Stale-fact handling is partial.
- No published, vendor-comparable benchmark, and no accuracy lead we can defend.
What we have and have not measured
On 50 held-out LongMemEval-S questions never used in Tephra development, Tephra answered 39 of 50 correctly (78%, 95% confidence interval 65-87%) with a gpt-4o-mini reader, and every evidence session was in its top 10 results for 46 of 46 answerable questions.
Method: LongMemEval-S cleaned, stratified 100-question subset; gpt-4o-mini reader over top-10 retrieved items; official GPT-4o judge prompt; one run, 2026-10-08; held-out questions are the 50 never used in earlier Tephra tuning; competitors run locally from open source under the same harness.
In that same-harness run, none of Tephra's leads over the other systems tested was statistically significant after correcting for multiple comparisons, and its margin over a plain keyword-search baseline was not significant either. We do not claim Tephra is the most accurate memory. We did not benchmark Supermemory, Zep, ChatGPT memory or Claude memory, and we do not compare ourselves with any vendor's self-reported numbers.
Frequently asked
Is Mem0 free?
Mem0 lists a free Hobby plan with 10K add requests and 1K retrieval requests a month. Starter is $19 a month and Pro is $249 a month, as read on 2026-10-10.
Is there a Mem0 alternative that is not for developers?
Tephra is built for people connecting AI apps they already use, with no coding beyond a connect command or a settings entry. It has no free tier and no self-hosting, so read the where-they-are-better section before choosing.
Did you benchmark Tephra against Mem0?
We ran Mem0's open-source version in a same-harness test with a weaker local extractor, and the difference was not statistically significant after correction. We make no claim that Tephra beats Mem0.
More comparisons
Sources
Competitor facts come only from the pages below, accessed 2026-10-10.
- Mem0 documentation overview: https://docs.mem0.ai/introduction (accessed 2026-10-10)
- Mem0 pricing: https://mem0.ai/pricing (accessed 2026-10-10)